IT REVISION

PART 1 - FUNDAMENTALS OF HARDWARE AND SOFTWARE

Explain the concept of Information Technology;

The term used to describe the hardware and software equipment used to access, retrieve, convert, store, organise, manipulate and present data and information. it is the use of equipment and programs to produce information

Distinguish among the major types of computer systems in terms of processing speed, storage and portability;

Computers are classified based on:

• speed (measured in gigahertz)

• reliability (ability to consistently produce accurate information)

• accuracy (the ability to produce correct information)

• storage

From highest processing speed, storage and lowest portability:

• Super Computers (for example, Cray) 

• Mainframes (for example, IBM zEnterprise System)

• Desktop systems. 

• Mobile devices (for example, laptops, notebooks, netbooks, smartphones, tablets and game consoles). 

• Embedded devices (for example, special-purpose systems such as controllers in microwaves, car ignition systems, answering machines). 

embedded devices: fixed in, built-in, microprocessors inside them that have special features that are activated when a button is pressed or a dial is turned, basically has control features

Explain the functions of the major  hardware components of a computer system;

Major components: 

• input: the process of taking data from the real world and entering it into the computer

• central processing unit: consists of the CU and ALU, responsible for processing data and turning it into information.

  • control unit - responsible for fetching and decoding input data, and controlling the flow of processes within the central processing unit

  • arithmetic and logic unit - responsible for carrying out the arithmetic and logical operations in the central processing unit

• primary memory (RAM and ROM): memory located on the main circuit board of the computer for quick access during computer processing. RAM is temporary and volatile (holds data that is being used for processing at that moment), while ROM is permanent and non-volatile (holds the BIOS)

• secondary storage: memory located outside of the main circuit board used by the user to store information for long time use. divided into local and cloud storage

• output: the process of retrieving information from the computer visually, audially or by another method

(a) Secondary storage devices: 

There are three types of secondary storage devices:

• magnetic: data is written onto magnetic material

• optical: data is obtained using lasers

• flash-memory: uses electrical signals

There are 4 magnetic storage devices that we need to know:

• hard disk: a type of magnetic storage, high speed, portable, large capacity, direct data acess

• magnetic tape: a type of magnetic storage, low speed, large capacity, sequential data access

• zip disk

• floppy disk

Optical Disks

• optical disks (CD, DVD and BluRay): a type of optical storage, BluRay, DVD, CD, in order of highest to lowest speed and capacity, direct data access

Flash-Memory

• flash drive: a type of flash-memory storage, high speed, large capacity, direct data acess

• memory card: a type of flash-memory storage, high speed, large capacity, direct data acess

Storage Device vs Storage Media

Device - manages the media, reads and writes to the media

• read/write heads

• flash drive

• cassette reader

Media - the material that stores the content

• hard disk

• floppy disk

• cd

• magnetic tape

• memory sticks

(b) Units of storage: 

• bits: the smallest unit of information a computer can process, either 0 or 1 

• bytes: 8 bits

• kilobytes: 1024 bytes

• megabytes: 1024 kilobytes

• gigabytes: 1024 megabytes

• terabytes: 1024 gigabytes

Explain how the major hardware  components of a computer system  interrelate;

They interrelate through the IPOS cycle:

• input: the process of taking data from the real world and entering it into the computer

• processing: the turning of data into information, done by the CPU

• output: the displaying of information on the computer screen or audibly

• storage: the storage of information for future use

You cannot have one without the other. You can’t process data without inputting it first, you can’t store information if you haven’t processed it, etc.

Evaluate the relative merits of cloud storage and local storage;

local storage: storage devices that are not based on the internet, but physically attached to the computer.

They are non-volatile and permanent. 

cloud storage: a module in which data is stored on remote servers and is only accessible by internet on the cloud.

Local VS Cloud Storage in terms of:

Capacity

• local storage has fixed storage; cannot be changed unless another device is bought and added to the storage

• cloud storage has easily expandable storage; can be expanded by paying more money for storage

Cost

• local storage has a fixed cost; it is a one time purchase

• cloud storage is usually a subscription; for the maintenance of cloud servers, it usually becomes more expensive over time 

Accessibility

• local storage is always accessible as long as you have the physical device with you

• cloud storage is dependent on the internet; cannot be accessed without it

Security issues

• local storage is susceptible to theft and environmental damage

• cloud storage, although it has encryption, is still vulnerable to hacking or other malware

Cloud storage 

Advantages

• increasable capacity

• not easily damaged, secure

• not needed with you physically to retrieve data

• easy to share and sync files

• files can be backed up

• password protected

Disadvantage 

• More expensive over time

• don’t have full control over your data (owned by the storage provider)

• able to be hacked

• unable to be used w/o internet

Local storage 

• easily accessible without the reliance of internet

• one time purchase/cheaper

• safer security to hacking 

Disadvantages 

• device damaged, says destroyed

• able to pick up viruses 

• Can be stolen

• has limited capacity

• must have it with you
  

Select appropriate input/output devices  to meet the needs of specified  applications;

There are two types of input devices, manual input devices and direct data entry devices:

Manual: the human uses them to enter data themselves

• mouse

• joystick

• light-pen

• touch terminals

• voice response unit (microphone)

• keyboard

• digital camera

• remote control

• pointing devices

• webcam

• sound capture

Direct:

• Optical Mark Recognition (OMR) 

• character readers (Optical Character Recognition, Magnetic Ink Character Recognition)

• Smart cards

• bar code reader

• document scanner

• sensors

• biometric systems

Visual output: 

Monitors

• resolution: the clearness/detail of the output, made up of pixels (tiny dots), 

• types: liquid crystal display (LCD), light emitting diode (LED), 

• sizes: from 14 inches to 19 inches

Printers 

There are two types, impact (involves the striking of a carbon/inked ribbon) and non-impact:

Impact: (good for carbon copies)

• dot matrix

• character

• line

Non-Impact: use a spray of heat

• inkjet

• laser

Special

• thermal - uses heat to print, e.g. receipts. fades after a while

• plotter - used to print geographical maps

• 3d

• microfilm: alternative to the printer, data is printed onto a roll of film and a special device is then used to view it

Audible output

• speakers

• headphones

• earphones

Explain the role of the different types of software in computer operation;

system software: software that controls how all other software and hardware work. divided into operating system, utility and translator

Operating System: a type of system software that allows the computer to efficiently execute application programs and manage hardware.

• Windows (95, 98, 2000, XP, Vista, 7, 8, 10)

• IOS

• MAC OS (8, 9, 10, X)

• Android

• Linux

• UBUNTU

• Unix

Functions:

• Provides a user interface

• Process Management - controls which processes are done and when 

• File management - controls the way files are organized on a computer

• Memory management - the allocation and creation of virtual memory when memory gets too full

• Input/output device management - manages I/O devices through drivers

• Provides security through the implementation of user authentication 

booting: the process of starting one’s computer. during this time, the computer checks for new hardware, runs test to see if everything works, and starts the operating system

utility software: perform the maintenance operations of the computer system. It is usually focused on analyzing, managing, maintaining, and controlling a computer system. Normally focused on a specific task.

These include:

• Antivirus Programs

• Disk Cleaners

• Disk Defragmenters

• Firewalls

• Backup & Recovery procedures

• Registry Cleaners

• System updates and patch management

application software: a set of programs designed to execute specific tasks for users. they solve end-user problems and are thus called end-user programs. divided into 5 types

general-purpose: applications that can be used by everybody. also called off the shelf 

customized general purpose: a general-purpose software that has been modified by a programmer to fit the needs of a user or organization

• e.g. addons in google chrome

special-purpose: organisations that are created for a specific purpose/industry and cannot be used beyond that purpose

• e.g. AutoCAD, PeachTree, Airline Reservation System

custom-written: This type of software is often called tailor-made or bespoke which is created specifically for a user or an organization by a programmer. It is designed to fit the specific needs of the user or organization. This enables a company to get their software exactly how they want it.

• requires training

integrated package: a set of applications bundled together 

• e.g. Microsoft Office, Lotus SmartSuite, Apple Works

Discuss the relative merits of the various types of user interface;

A user interface is the part of the computer (hardware or software) that interacts with the user. The user interface is sometimes more formally called the Human-Computer Interface (HCI). The user-friendlier a HCI, the easier it is for a user to use.  The interface can be graphical, text-based, or audio-video-based, this means it can be a hardware interface, a software interface, or a combination of both.

Hardware: 

• touch screens

• specialized keyboards (braille)

• sensors

Software:

Command line (uses commands to communicate with the computer)

• Advantages: fastest to process information, commands can be entered quickly if user is familiar with computer system

• Disadvantages: have to memorize commands to work efficiently, limited choice in input devices (keyboard), not user friendly

 menu-driven (uses pull-down and pop-up menus to communicate with the computer)

• Advantages: don’t have to remember commands, more user friendly than command line, variety of input devices can be used 

• Disadvantages: slower to process than command line due to the menus, still have to remember where certain commands are under the menus

graphical user (uses windows, icons, menus and pointers to communicate with the computer)

• Advantages: most user friendly, don’t have to remember commands

• Disadvantages: slowest because of the WIMP

  • icon: a graphical image that usually leads to a text or file

  • window: part of the screen

 Touch

• Advantages: user friendly, don’t have to remember commands

• Disadvantages: slow

Evaluate the suitability of a given computer system for a specific purpose; 

Basic knowledge of system specification  needed for purposes such as: 

• to run a video game: multi-core processors with GHz speed for better performance, dedicated graphics card for good visuals, large RAM (8 GB RAM) for larger games, SSD for large games, keyboard, mouse, monitor

• web browsing: multi-core processor with sufficient (GHz) speed, large RAM, moderately sized hard drive, web browser (such as Safari, Google Chrome), keyboard, mouse,

• graphic design: multi-core processors with GHz speed for better performance, dedicated graphics card, SSD for faster file access and capacity, software like adobe Photoshop, GIMP, mouse, monitor

• video editing: multi-core processors with GHz speed for better performance, dedicated graphics card for good visuals, large RAM (16 GB RAM), software like adobe after effects, final cut pro, keyboard, monitor

• desktop publishing: multi-core processor, dedicated graphics card, sufficiently sized ram (8 GB), software such as microsoft publisher, google slides, adobe page maker, keyboard, mouse, monitor

Criteria:

(a) Processing speed (CPU type and speed); 

(b) Memory (RAM);

(c) Secondary storage (capacity and 

speed);

(d) Types of software; and,

(e) Input/Output devices

Troubleshoot basic computer hardware problems;

Before working on the process of elimination, users should:

• Restart/Refresh

• Write down error codes

• Check cables

• Write down the measures taken already 

N.B. Never turn off your computer when something is wrong! You may lose work.

Cable problems

•  loose cables

• faulty cables

• power strip not turned on, or not working - test with another device to see

• cables malfunction due to shortage

Monitor problems

• improper settings (e.g brightness too low)

• HDMI/VGA cable loose/faulty

• monitor not turned on (check monitor light)

• monitors should be turned away from strong light sources such as fluorescent lamps and radios which make the screen difficult to read

Printer problems 

• ink cartridges finished

• paper finished, or stuck inside the printer

• wireless printer not connected to wifi

• wired printer cable not attached

• printer driver not working, or wrong printer driver selected

• if the quality is low, check the quality options being used on the computer

• ensure printer not open

Battery problems 

• battery dead

  power cable faulty or loose

Some troubleshooting situations

1. Wireless printer not printing

Solution 1: Connect a USB type A cable to the printer for wired  printing, just to check if the printer is not the problem

Solution 2: If the printer is a wifi based printer, ensure that the printer is connected to the modem. 

2. Computer is frozen

Issue: An app is not responding

Solution 1: Soft power down by holding down the power button

Solution 2: Close the applications open with Ctrl + Alt + Delete to open task manager then close the application forcefully

3. Keyboard/mouse stopped working

Issue: The USB cable for the mouse is not connected properly to the computer

Solution 1: Check to see if the USB cable is properly connected to the port on your laptop/PC. If it’s not, the red light under the mouse will be off. If it isn’t, plug it in correctly.

Solution 2: The driver for the mouse might need to be updated. Go to the manufacturer of the mouse, get the driver for your model and change it

Solution 3: Try connecting the mouse to a different device to see if the USB port is working or if it’s the mouse

Solution 4: Restart the computer to fix the problem 

4. The screen is blank

Issue: The monitor is not on

Solution 1: Check if the HDMI/VGA cable is connected to the computer properly, it may be loose.

Solution 2: check if the brightness is up and not all the way down

Solution 3: The computer is in sleep mode, click or press any button to get out of sleep mode

4b) Wireless Monitor

Solution 4: If the monitor is wireless, you can also try wired connection

5. There is a dinosaur on the computer browser and I can’t access my website

Issue: There is no internet connection

Solution 1: Check if the computer is connected to the wifi in the settings menu, you can also check if the wifi connection is turned off/airplane mode

Solution 2: Check if the modem is connected properly to the outlet, unplug and replug the modem if the modem is connected properly and there’s still no wi-fi

Solution 3: Ensure that the computer is within range of the modem to get connection

Solution 4: The page that you’re trying to connect to may be slow, so try refreshing the page, trying a new tab or even trying a new browser

Solution 5: The firewall could be blocking you from the site, so you can disable your antivirus software/firewall software to access the site

6. Computer shows 1990 instead of 2022.

Solution 1: The cmos battery (part of the CPU that deals with time) is dead or dying

Solution 2: If you have a new computer, your timezone may still be in the country you bought it from, which might be causing this issue. Your timezone isn’t properly synced, it should be synced to Eastern Standard Time or Bogota.

PART 2 - INFORMATION PROCESSING

Distinguish between data and information;

data: raw, unprocessed facts

information: processed data

• data processing: the manipulation of data to obtain information

• information system: any record keeping system (manual or digital)

Sources of data and information:

People, places, and things, but also:

• formal/informal communication: word of mouth, meetings

• publications: journalists, newspaper, articles/blogs

• questionnaires: opinion polls

• labels: calorie amount, nutrient composition, ingredients, quantities

Document types: 

• source document: a document used to collect, store and share information

• turnaround document: a printed document with machine readable information on it that needs information to be added to it by a human before it is fed back into the computer and processed (e.g. utility bills, checks, lottery, mcq papers). They are used to verify the accuracy of information already entered and update documents with more information. This type of document can be created with an OMR and and OCR combined.

• human-readable: hard copy texts that can be understood by a human (e.g. physical stuff like books)

• machine-readable: soft copy documents that can be understood by a computer  (e.g barcodes, QR codes)

Document forms:

•  hard copy (tangible): information output onto paper, can be touched and held. permanent. easier to keep track of

• soft copy (intangible): this refers to information output on a screen that can be accessed on a computer. more cost effective than hard copies

evaluate the reliability of information obtained from online sources;

• Relevancy: should be what the user is looking for

• Currency: it should be relatively recent or updated recently, links working

• Author/Credibility: what are the author’s credentials? are they authorized to be giving this information?

• Bias: is the author speaking facts or stating an opinion?

• Cost-effective: the value of the information should cost more than what it took to get the information

differentiate between validation and verification of data;

Sometimes, as humans make mistakes, data is entered incorrectly into the computer.

These data entries may be:

• accidental (an honest mistake) 

• deliberate (a purposeful mistake, usually used to sabotage)

And there are two types of errors that cause incorrect data to be entered:

• hardware errors (intermittent faults that corrupt data - e.g. bad sector, bad memory, power surge)

• software errors (software malfunction, erased, corrupted)

Examples of Errors

Correct Sentence-I went down the street and saw my friends playing cricket.

Typographical errors- I sent down the street and saw my friends playing cricket.

Transpostional errors- I wnet down the street and was my friends playing cricket.

To mitigate these errors, there are two things we can do:

data validation: the computerized process of checking data that has been entered to see if the data has errors. It does not check for the accuracy of the data, just the reasonableness of it.

data verification: the human process of checking data that has been entered to see if the data has errors (for example, transcription errors)

DIFFERENCE BETWEEN DATA VALIDATION AND VERIFICATION

1. Validation is done by a computer and verification is done by a human

2. Validation checks to see if data is not necessarily correct, but acceptable. Verification checks to see if data is actually correct.
   
   
   
   
   
   
   

identify appropriate validation and verification checks given a particular scenario;

There are numerous types of data validation:

• length check (checks if the data is the appropriate length - in terms of characters [e.g 5 characters long])

• range check (checks if the data is the appropriate range - like ages of a teenager [13-19])

• reasonableness check (checks if the data is reasonable - for example the ages of kindergarten children cannot be too old [like eight])

• format check (checks if the data is in the right format - for example liscence plates, 4 numbers and then 2 letters)

• data type check (checks if the data is the right type- number, currency, string, etc.)

• consistency check (checks two fields for discrepancies and to see if they match up with each other- for instance D.O.B and age)

• presence check (checks to see if data has been entered into a field at all)

There are two types of data verification:

• double-data entry: this involves entering the data twice, each entry done by a different person, and checking them against each other to see if the data is a match (and therefore correct) [e.g. being asked to enter your password twice]

• proofreading: this involves checking if the data is correct by reading it over

select appropriate file organization for particular application

Random file organization

-   In random file organization, records are stored in random order within the file. there is no sequencing to the placement of the records

• Data can be quickly accessed whenever it goes to Main Memory

• e.g. you have a big folder with alot of files inside, you just go in the folder and take the file out 

• e.g quick access 

• To access a file stored randomly, a record key is used to determine where a record is stored on the storage media.

• 
  

Advantages of random file access

Quick retrieval of records.

The records can be of different sizes.

Serial file organization

-     The records are arranged one after another, in the order in which they were added. That is, they have not been sorted into any particular order.

• Examples of serial files (also called unordered files) include unsorted invoices for customers for the day, and a typical shopping list. Serial files can be stored on tape, disk or in memory.

Advantages of serial file organization

• It is simple, cheap

Disadvantages of serial file organization

-          It is cumbersome to access because you have to access all proceeding records before retrieving the one being searched.

-          Wastage of space on medium in form of inter-record gap.

-          It cannot support modern high speed requirements for quick record access.

file - a container in a computer system for storing data, information or programs 

sequential file organization: a type of file organization in which the files are stored based on one or more primary keys

• e.g. sorting by customer number, class registers sorted on last name

• e.g. magnetic tape
  

File access methods: 

sequential: data has to be retrieved in the manner in which it is stored

• note that serial access does not exist. it is simply sequential access. so files organized serially and sequentially are accessed sequentially

direct: accessing a particular file by entering its specific/unique address in storage

• Where each file has a specific location or unique address in storage

• e.g.  you have a big folder with a lot of files inside, you have to type in the name for the file/address of the file within the folder to find the filethe best for frequent updates

random: going to file management and scrolling down to select a file, don’t consult search bar

index-sequential: data is retrieved sequentially but using an index file to speed up the process

Types of Data processing 

Batch Processing - processing large amounts of data automatically

e.g. processing your utility bills, because you get billed every certain period of time (monthly, weekly, fortnite)

e.g. payroll because you get billed every certain period of time

Transaction processing - data transferred between two or more computers

e.g. of apps, paypal, e-commerce (withdrawals, deposits, transfer, buying and selling of goods/services over the internet)

Distributed - the processing is shared between many computers on a network. Distributed data processing (DDP) is a technique for breaking down large data sets and storing them across multiple computers or servers 

e.g. the computer lab at campion, files are shared in the common z drive

e.g computers in a bank or organization

Online - data transfer or processing that occurs over the internet. online signifies interactive. might have delays

Real Time - processing data that requires immediate response 

Application areas: 

archiving: this is the process of removing old files that are no longer in use from a database and placing them in another area long term. data is often stored serially and accessed serially or directly based on the device used

payroll file: used to calculate the wages of each employee, usually stored sequentially based on some kind of ID and accessed index-sequentially or directly

real-time systems: these are systems that depend on the processing of data in that moment, such as traffic control systems and airline reservation systems, data is often stored serially and accessed directly

PROCESSING SYSTEMS

1. Industrial Information Processing Systems:

   • Definition: Industrial information processing systems are designed to handle data and control processes within industrial settings such as manufacturing plants, refineries, and utilities.

   • Examples: petrochemical refinery

2. Scientific Information Processing Systems:

   • Definition: Scientific information processing systems are used for data analysis, modeling, simulation, and visualization in scientific research and engineering.

   • Examples: weather forecasting

3. Commercial Information Processing Systems:

   • Definition: Commercial information processing systems are used in business and commerce for tasks such as accounting, customer relationship management (CRM), inventory management, and sales processing.

   • Examples: banking industry managing user accounts

4. Process Control Information Processing Systems:

   • Definition: Process control information processing systems are focused on monitoring and controlling industrial processes to ensure efficiency, safety, and quality.

   • Examples: sequencing wash cycle tasks in a washing machine

5. Automation Information Processing Systems:

   • Definition: Automation information processing systems involve the automation of tasks or processes that were previously performed by humans, often using machinery or computer systems.

   • Examples: using robots to assemble car components
     

PART 3 - COMPUTER NETWORKS AND WEB TECHNOLOGIES

distinguish among types of networks;

Types of networks (local area network, metropolitan area network, wide area network, mobile network). 

• local area network: a network that connects devices in a small geographical area (like a home)

• wireless local area network: a network that connects mobile devices to each other and the internet wirelessly

• metropolitan area network: a network smaller than a WAN but bigger than a LAN, connects devices within cities (e.g. universities, connects devices within Kingston). used to connect WANs and LANs together

• wide area network: a network that connects devices over a large geographical area (like over countries. e.g. internet)

• peripheral area network: a network that connects mobile devices to the internet and each other wirelessly over a small geographical area

stand alone computers: computers not attached to a network

To connect to a LAN, you need:

• network cabling (ethernet cables)

• network interface card

• switch/hub

• file server

• system software

Concept of mobile network as radiobased common carrier. 

The communication within the mobile network relies on radio waves for transmitting and receiving signals. Radio waves are high frequency, long-distance microwaves that travel through out the atmosphere. Microwaves (or radiowaves) travel in straight lines and bounce off of satellites to arrive at their destination..

Overview of mobile networks: from 2G to current. (Knowledge of the inner workings of mobile systems is NOT required) 

Wireless network technologies (for example, Bluetooth, Wi-Fi, hotspot). 

bluetooth: designed to replace cables, allows mobile devices to connect to each other to share information wirelessly over a small geographical area

wi-fi: stands for wireless fidelity, allows mobile devices to connect to the internet wirelessly over a wireless network

hotspot: a public area that offers internet access over a wireless local area network

Level of privacy

intranet: a private network created by an organisation that is only accessible by members of that organisation, extranet: a portion of an internet that is accessible to users outside of an organisation through the entering of a serial number of key. facilitates the sharing of information, collaboration and goodwill.

Internet: a global network that connects millions of computers all over the world

data communication: the sending and receiving of data/information between two or more computers

upload: to send data from your computer to another computer

download: to receive data from one computer to your computer

Network Topologies (from slowest/worst to fastest/best):

• bus

• ring

• star

• mesh

• hybrid

Explain the functions of the basic components of a network;

Basic components and functions:

(a) Transmission media:

There are two types of transmission media:

Wired: 

• twisted pair (slowest, used in home settings, telephone lines, also called ethernet cables, voiceband)

• coaxial (made of copper, medium speed, broadband)

• fibre optic (made of glass, fast speeds, moisture and light resistant, broadband)

Wireless:

• infrared: a type of electromagnetic wave having short wavelengths that is used for data transmission. two types are scattered and direct line of sight

• microwave: a type of electromagnetic having short wavelengths used for data transmission, especially in mobile devices and is used alongside satellites. data is transmitted as information is reflected off of one microwave station to the next

• satellite: similar to microwave transmission, except satellites in space are used

• bluetooth

switch: a device that expands the amount of devices that can be connected to a router, forwards data packets to different devices 

modem: modulator/demodulator. convert analog signals into digital signals and vice versa. assigns IP addresses and facilitates a connection to the internet through the ISP

router: responsible for the traffic control of the network, transfers data packets from the modem to their 

• routers have a built in modem!

destination, assigns MAC addresses

Network interface card/adapter: built into the computer usually, facilitates the connection of the computer to a network with use of an ethernet cable

To connect to the internet you need:

• Switch/hub

• Router

• Modem

• Network Interface Card

• Internet, provided by the ISP

Protocols

Govern the way information is sent and received over the internet

• HTTP

• TCP/IP (break down data and send it over the network then build it back up)

• BGP

Assess the importance of mobile communication technologies as a  component of modern communication networks;

Suitability of mobile networks to various  applications

education

• online educational apps that suit everyone’s needs

• online school

• school management systems such as moodle and canvas

commerce

• portable

• no longer need to carry cash

• organisations can make their customers feel more connected to them with the use of codes

journalism

• subtle

• inexpensive

• people often feel less intimidated by it rather than a full blown camera

explain the interrelationship among key Web technology concepts.

World Wide Web: millions of webpages linked together over the internet

Hypertext Markup Language: the language used to construct web pages on the internet

Hypertext Transfer Protocol: protocol that governs the way multimedia files are transferred over the internet

Hyperlinks: links that take you to other websites or files

Web Server: hardware and software that respond to client requests using HTTP protocols

Web Page: a singular hypertext document in a website

File Transfer Protocol: governs the way in which files are sent and received over the internet

Web Browser: an application that allows a user to access certain files over the internet

Uniform Resource Locator: also known as the internet address, it consists of the domain name and extension of a website

Upload: sending of data to one computer from another computer

download: receiving data from one computer to your computer

Email: electronic mail, a form of electronic communication 

cache: a temporary storage space that stores information from websites you’ve already visited to reduce loading time

Services of the Web

• Instant messaging

• Communication (voice over internet protocol)

• Email

• World wide web

• HTTP/FTP

PART 4 - WORD PROCESSING & WEB PAGE DESIGN

create a document using content from a range of sources; 

Importing text (combining documents)

• copy (ctrl + c), cut (ctrl + x), paste (ctrl +v )

- N.B. if you cut something, it is automatically copied to the clipboard

Typewritten text, images and other objects. 

use appropriate document formatting features; 

Formatting features: 

Font types (design of the font - e.g. Arial, Jua), font style (a modification added to a font type - bold, italic, underline) and sizes, colour, underline, bold, italics, highlight, uppercase, superscript and subscript

•  these can all be found in the home ribbon of word, the font types, sizes, colour and some of the styles (e.g. bold, italic, underline, superscript, subscript) can be found in the font ribbon

• uppercase is found in the font ribbon at the bottom, the upper case and lower case A icon (Aa) has a bunch of features like uppercase, lowercase, capital letters, sentence case, etc.

• heading 1, heading 2, etc. can be found in the styles ribbon

Tab stops (control the indent of the page when the tab button is pressed), bullets and numbering, line spacing, justification (left, right, centre, full)

• can be found in the paragraph ribbon on the home tab

word wrap

1. select the picture or text you want to edit

2. go to picture format

3. under arrange, you should see wrap text

page size, margins, page and section breaks, 

• can all be found in the layout tab under page setup

page numbers, headers, footers, footnotes and endnotes.

• headers, footers and page numbers can be found in the insert tab, under headers & footers

• footnotes and endnotes are found in the references tab, under footnotes

 use appropriate editing features to structure and organize a document; 

Drag and drop editing: perform block operations on selected areas of text within a document. 

• copy (ctrl c)

• paste (ctrl v)

• cut (ctrl x)

Use search and replace functions appropriately to edit a document. 

1. in the home tag, check the far right of the screen and you’ll see a magnifying glass

2. click on the magnifying glass and find the option find & replace

3. enter the word you want to find, and what you want to replace it with

4. either click replace or replace all

Use of tables, table styles, shading, borders, row and column insertion, split cells, split tables, text direction and cell margins, cell size. 

1. Go to the insert tab

2. Under the tables section, you’ll see a table, click on it and you can choose how many rows and columns you want

3. To edit the table in terms of styles, shadings, borders it’s under table design

4. And for split cells, tables, text direction and cell margins and cell size, they can all be found under table layout

• N.B that table layout & design are only available when a table is highlighted

Use of columns (one, two, three, left and right columns, column breaks).

1. Select the text you want to make this change to

2. Go to the layout tab

3. Under page setup, you’ll see a column icon, tap on it

4. Choose how many columns you want your text to be divided into

5. As for column breaks, they are in the same layout tab under the icon breaks in the page setup section

use the review feature of a word processor to enhance document readiness; 

Spell and grammar check, thesaurus, word count

• All under the review tab under the proofing section

language setting, comments, track changes

• They are all under the review tab in their respective sections

• Comments under the review tab under the comment section - you can leave comments on certain sections of text

• Track changes nder the review tab under the tracking section - when you track changes the new changes you make to the document become highlighted in a different color

• Language setting has its own section under the review tab - you can change your preferred language

appropriately use features that allow the protection of a document; 

Automatic save and backup copy

1. At the very top of the screen in the title bar, next to the undo and redo buttons, there is a toggle switch that turns autosave on and off

edit restrictions – password protection. 

• file > info > protect document > encrypt with a password

generate table of contents for a document; 

Auto table of content

• references > table of content > auto table of content

use mail merge feature in the preparation of a document for a variety of situations;

Creation of primary documents and data files in mail merge application. Field names

Steps to mail merge

1. Create your source or primary document that is the base of the letter that you will send to everyone

2. Go to the mailings tab and select mail merge/start mail merge and then select recipients

3. Import the field names that you will be using (usually from a database) from a data source/source document)

4. Insert the field names into the parts of the source document

5. When complete, press finish and merge, you can view individual letters and send them by email

Create a fillable electronic form for online use; 

Use of content controls, such as check boxes, text boxes, date picker, drop-down lists, and command buttons.

1. Go to developer tab

2. If you don’t see developer tab enable it by going into settings and selecting the developer tab

3. From there you are free to design your form with check boxes, text botes, data pickers, drop downs, etc

plan a website structure and organization of page; 

When planning a website, you should always think about these things first:

• Reasons for the website

• The intended audience

• Number of web pages desired (no more than 3 pages)

• Content of each page

• Layout of the web page. 

Ceate simple web pages using a variety of design features; (The use of HTML coding is not required.) 

Choosing an appropriate design for a page. 

style="property:value" 

The different properties are:

• backgroundcolor

• font-family

• color

The styles are for headers (h1, h2), paragraphs (p1, p2) and just text in general

Inserting and deleting text and graphics

<img src= ”link to the image” width ”x” height ”x”>

Wrap text with image. 

Create home page with hyperlinks

insert hyperlinks within different locations of a typical web page; 

Link to another web page. 

<a href=”link”> this selected text will take you to another web page </a>

Link to a location within the web page

Link to an email address

<a href=”someones@gmail.com”> this selected text will take you to the email screen automatically </a>

Link to user-created files. 

evaluate a website for accuracy, user friendliness and effective display

Considerations for publishing a website: 

• Verify that all the hyperlinks work correctly

• Use a test audience

• Verify that all content is up-to-date

types of section breaks:

PART 5 - SPREADSHEETS

explain the purpose of a spreadsheet; 

Purpose of a spreadsheet: a spreadsheet is a grid of cells consisting of rows and columns that hold accounting or financial data. It captures displays and manipulates and performes calculations on data to create information in the form of charts and other media.

use appropriate terminologies and notions commonly associated with spreadsheets; 

Common features: 

• workbook (a group of worksheets)

• worksheet (a singular excel page in a worksheet)

• column (a group of cells extending vertically)

• row (a group of cells running across the screen, horizontally)

• cell address (the specific row number and column letter of a cell - e.g. B4)

• cell range (a group of selected cells - you can click on a row or column to highlight all cells in that row/column)

• label (any data that begins with/includes a letter)

• value (any data that only has numbers. values are used in calculations, so not every number is a value e.g. telephone numbers aren’t values)

• formula (use arithmetic operators to manipulate numbers - e.g. =[A1+A2])

• function (a built in mathematical formula used in excel (e.g =SUM, =AVERAGE, =MAX, =MIN, no arithmetic operators)

• argument (a cell or range of cells used in a function)

se basic pre-defined systems functions; 

Including 

• sum =SUM (A1:A2)

• average =AVERAGE (A1:A2)

• date =DATE(year, month, day) - another thing to note is =TODAY() gives you the current date

• max =MAX (A1:A5)

• min =MIN (A1:A5)

• count =COUNT (A1:A5) - count only counts cells with values in them

• counta =COUNTA(A1:A5) - countA counts all cells, even blanks and texts

• countif =COUNTIF(range of cells, criteria) - countif counts cells that meet a criteria

• vlookup =VLOOKUP (cell you want to look up, cell range of table you want to look it up in, the column number relative to the first column containing the information you want, true/false [approximate match]) - vlookup looks for a value in another column, finds that value and brings back an associated value

•  pmt =PMT(rate (if the thing is in years divide it by 12), nper (number of months for payment), loan value)

• if IF(cell=criteria, value if true, value if false)

create advanced arithmetic formulae; 

Formulae including addition, subtraction, multiplication, division, and use of brackets

replicate (copy) formulae into other cells; 

Relative addressing: in relative addressing, when the formula is copied down to the next cell, the cell values change as the formula is adjusted

absolute addressing: in absolute cell addressing, when the formula is copied down to the next cell, the values do not change. it is done by placing a dollar sign ($) infront of the rows and columns you desire to keep

naming of ranges: to name a range, highlight a group of cells, find the name box in the top next corner next to the formula bar, and enter the name you want that range of cells to be called

 Effect of move, copy, delete operations on formulae

• moving would affect the cell value of the formulae, for example moving something from A1 to B1 would cause the formula to read B1 instead of the previous A1

• copying a formulae will not damage it

• Deleting a part of a formulae that is important will cause the output of the formula to display an error or be incorrect

 manipulate columns and rows; Insert, delete and modify columns and rows. 

• insert: to insert a row or column, highlight all the cells of the column by right clicking on the column letter/row number, and press insert. for rows, the values underneath it are shifted downwards, and for columns, values after the insert are shifted to the right

• delete: to delete a row or column, highlight all of the cells by clicking on the column letter/row number and pressing delete. this causes row values to shift upwards, and columns to shift to the left

manipulate data in a spreadsheet; 

Numeric Data formatting (currency, accounting, percentage, comma, decimal places). 

• to format cells, right click on the cell and go to format

• from there, you can see all of the types of cell formats including:

• currency (numbers with dollar signs and decimals, left aligned)

• accounting (also numbers with dollar signs, but the dollar signs are placed on the far right of the cell and negative numbers look differently)

• percentage (the value is divided by its total and multiplied by 100)

• comma (simply means when the number has enough digits a comma separates them)

• decimal places (how many numbers are after the decimal place)

Sorting data (primary field, secondary field, ascending vs descending order). 

To sort data (regularly - in ONLY ONE FIELD)

1. Go to the head of the column you want to sort, there should be an arrow next to the text

2. Click on it

3. A dialogue box comes up asking if you want to sort in ascending or descending order, you can choose

To sort data (Advanced - MULTIPLE FIELDS) )

1. Go to data tab, go to sort

2. Press the sort icon

3. A dialogue box comes up, where you can select the column you want to sort, and what order you want to sort it in, whether ascending (A-Z) or descending (Z-A)

4. This is your primary field

5. You have the option of then sorting by another field, which in this case would be your secondary field, you can once again sort ascending or descending

Filtering data (multiple criteria, complex criterion). 

To filter data (regularly - one field)

1. go to the head of the column you want to filter, there should be an arrow

2. click on the arrow, and a dialogue box pops up

3. here you can deselect the fields that you don’t want to show up, therefore filtering them

To filter data (advanced, multiple criteria)

1. Create a filter criteria, by compiling all the column headings together, and underneath the column headings enter the data that you want to filter out of a cell range

2. Go to the data tab and press advanced filter

3. Select the cell range as list range, the criteria range as the filter criteria you created

4. If you want to copy to another location, select the option, then select where you want to copy the filtered results to and then press ok

Pivot Table (create one and two dimensional pivot tables, create frequency distribution from data and create pivot chart

1. To create a pivot table, go to insert, click pivot table

2. Select the range of data you want to create the pivot table with and press insert

3. You will have a blank pivot table, drag and drop the rows, columns and values you want (a one dimensional pivot table only has a row and values or a column and values, a two dimensional pivot table has all 3)

4. Right click a field data and grouping thevalues in the rows by a certain number of values creates a frequency distribution

5. create a pivot chart from the table by going to insert, pivot chart, and selecting the pivot table data

perform charting operations;

Select appropriate chart types: 

• Column charts (vertical bars), Bar charts (horizontal bars) - used to compare data

• line graphs, scatter, area - show how data evolves over time

• pie charts - parts of a whole

Labelling charts: 

• graph titles

• labels on axes

• data labels. 

9. Manipulate one or more worksheets. 

Use of one or more worksheets to solve problems involving some of or all of the functions and operations listed above. Linking of two or more worksheets to solve problem

to link two worksheets,

1. Type in the formula bar an equal sign, open bracket, the table name you want to link, followed by an exclamation point, and then the cells in that table you want to make reference to)

PART 6 - DATABASE

explain the concept of a database; definition and purpose

A database is a repository of information made up of a collection of related tables that allows a user to store, organize and manipulate data.

• the program that is responsible for this is called a database management system (DBMS) and includes applications like microsoft access, lotus approach, etc.

It is cost efficient, simple to use, easy to find and correct mistakes, quick at processing, can be protected.

use terminology commonly associated with a database; 

Database terminology: 

table: a collection of related records in a database

• also called a relation

row (record): a collection of related fields in a database

• also called a tuple

column (field): a singular cell of information in a database

 primary key: a unique field in a database that is used to identify each row

secondary key: a candidate key that was not chosen to be a primary key

candidate key: a unique field in a database that was not selected to be the primary key but has the qualities of one foreign key: a field that exists in another table as its primary key

composite key: a primary key that consists of two or more fields together.

Data types: 

• numeric/number

• text (Short text, long text)

• yes/no/boolean/logical field 

• date /time

• OLE Object (For multimedia files)

• lookup wizard

• hyperlink

• Autonumber

• currency

create a database;

Table structure with at least three data types and populated with at least 25 records. 

Modify a table structure: adding new fields, deleting fields, changing field definitions. 

• Deleting fields: Right click on the row you want to delete, press delete record

• Inserting fields: Right click on the row you want to insert another row below, press insert

• Changing field definitions: go to design view, find the field whose definition you want to change, go to the description column and edit it

Establish primary keys. 

1. Go to design view

2. Select the field you want to be the primary key

3. Under table design, find tools and you’ll see the primary key icon

4. Tap on it to make it the primary key

Establish relationships: show the joins between tables (one-to-one and one-to-many). 

To establish a relationship,

1. Go to database tools, select relationships

2. If the tables aren’t already there, you can insert them by left clicking on the page and pressing show tables

3. Drag the fields from each table to establish a relationship

4. a dialogue box pops up, showing you your relationship (one-to-one, one-to-many), at the bottom select the check to enforce referential integrity

manipulate data in a database. 

(a) Forms: 

(i) Use of form wizard only; 

• create > form wizard 

(ii) select suitable fields;

• select the fields you want in your form in the form wizard by double clicking on them or pressing the arrow

 (iii) use of sub-form. 

• this occurs when you use two tables to make a form

• enter all the fields from both tables into a form, then hit next

• allows you to group based on tables, so the table you group by will be the form and the other table will be the subform

• click finished

(b) Queries: 

(i) more than one criterion

1. Go to create, then query design

2. Select the tables you want to use, double click on the field names to put them in the query box

3. In the criteria field of the query box, type in the different criteria you want enter. You can either type them both in the criteria field (meaning both have to be met) or you can type one in the “or” field (one or the other can be met)

4. You can also sort the data if you wish, you can sort each field

(ii) use of select

(iii) use of calculated field

1. To calculate a new query, repeat the steps above (from 1-2)

2. In the query box, type in: [New Field Name]: [Calculation of other two fields]

3. For example: Total Cost: [Cost]*[Quantity]. There must be square brackets around the two fields being used for the calculation, but there are none around the new field. This is sensitive and field names must be written exactly as they appear with no errors

(iv) two or more fields involving the use of relational and logical operators

1. To create a query using AND, put more than one criteria in the criteria box when creating a query

2. To create a query using OR, put one criteria in the criteria box and another in the “or” box

3. To use other operators, go to the ribbon of query design, select totals. Then in the query box another row named group by will show up, you can group by sum, avg, min, max, count, etc

(c) Reports: 

(i) use of report wizard;

• Create, report wizard

• select the fields in the tables you want in your report

(ii) use of sorting, grouping, statistical and summary features, for example, count, sum, and average; 

• in report wizard, you are able to group by a specific field name by right clicking the one you want to group by

• after that, you can use statistical and summary features by clicking on summary options, you can do sum, avg, max, and min

(iii) report generated to screen, printer and file; and

• just go to print preview and select the print icon in the ribbon

(iv) renaming of report title

• simply go to report layout and right click the title to edit and change it

PART 7 - ICT 

outline the concepts of computer security, cybersecurity and computer  misuse;

Computer security: the protection of computer hardware and software from accidental or deliberate damage, theft or corruption

cybersecurity: the protection of a computer system from cyber threats, which are attempts at exploiting a computer system’s vulnerabilities over the internet

Elements:

vulnerability: a weakness or flaw in a computer system that may be exploited

Points of Vulnerability

• external: natural disaster, power surges, terrorist attacks

• internal: lack of security cameras, weak firewalls, unlocked doors at businesses, no passwords, no VPN

threat: the potential of a vulnerability in a computer system being exploited

attack: a successful threat, essentially, a vulnerability that has been taken advantage of and damage has been caused to a computer system 

countermeasure: measures put in place to ensure that attacks never happen, and to reduce a computer system’s vulnerability

proprietary data: data used exclusively by an organization

Computer misuse by individuals and groups/organizations. (Computer misuse is the broad topic under which a computer is used to cause harm to a computer system or individual)

Under the topic of computer fraud:

• Propaganda: the use of electronic devices to spread potentially harmful or beneficial information about a certain person or group to push a particular opinion. often used in politics

• Identity theft: the use of electronic devices to steal personal information such as credit card information and use it for nefarious means such as expensive purchases all while pretending to be the person in order to not raise suspicion

• Software & music Piracy (Copyright infringement): the unlawful sharing or downloading of software or music files on the internet in direct violation of copyright laws

• Phishing: the use of fraudulent emails or messages pretending to be from a reputable company or organisation with the intent of tricking people into entering their personal information. this personal information is often used for nefarious purposes.

• Financial abuse: when the perpetrator of a scheme purposefully locks their victim outside of their financial accounts, usually holding it over their heads in exchange for something

Denial of service attacks: this is an attack on a network that involves flooding it with so much traffic that it is unable to process it all, slowing down the network significantly or even crashing it.

Industrial espionage: when a company uses electronic devices to illicit sensitive information from another company such as marketing ideas, sales, etc. in order to use it for their own benefit

Electronic eavesdropping: the use of electronic devices for unauthorized monitoring of electronic communications between two or more parties without their knowledge or consent

Cyberbullying: the use of electronic devices to send malicious remarks/comments and make a person feel badly about themselves

Obscenity: the publishing of unsavory, sexual, inappropriate material to the internet which can then corrupt someone’s mind

Data theft: the use of electronic devices to steal confidential information to compromise someone’s privacy

Encryption: the process of coding a message to make it unreadable, unless decrypted using a software key

violation of privacy: the direct and inappropriate intrusion into someone’s private life

assess the potential impact of computer systems misuse based on the main entities impacted; 

Misuse: (a) Cyberbullying, copyright infringement, data theft, denial of service attacks, transmission of viruses and malware, identity theft, online publication of obscene materials, phishing attacks, software and music piracy, financial abuses, violation of privacy, propaganda, electronic eavesdropping, industrial espionage

(b) Entity impacted: individual, organization, government.

escribe suitable countermeasures to mitigate effects of identified threats; 

Virus: a program that inserts itself into another program with the intent of damaging or corrupting the file. there are three types: ones that affect program files, others that affect system files, and others that affect macro files.

• WORM: a virus that does not need a program to attach itself to in order to wreak havoc, instead it attaches itself directly to memory. they replicate.

Malware: an overarching term that describes any software designed to steal sensitive, financial, and personal information and damage a computer system and its data

assess the effect of automation on job security; Job loss vs productivity gains in skilled and unskilled job categories.

Positives:

• More can get done in less time with automation

• Automation, depending on the career is less likely to make mistakes

• Overall end up being more cost effective 

• People end up being rehired to operate the automations anyway

Negatives:

• People with unskilled, repetitive and dangerous occupations are more likely to lose their jobs, have to relocate. that isn’t to say that skilled occupations don’t face the same dilemma, but it is less likely for unskilled people

• People may have to be retrained- may result in slower work process

describe the roles of various personnel in computer-related professions;

Network Engineer: responsible for the physical maintenance of the computer network, installs new systems and services computers.

Computer Programmer: works with the computer system analyst to write the code that will be used to develop a program

Computer Support Specialist: specialists who help users who have technical issues with their computer system

Computer Systems Analyst: observe and inspect a particular system and make note of any improvements or changes that need to be made

Network Administrator: responsible for maintaining the network, and making sure that everything is running smoothly. they set up MANs, LANs, and WANs, and security details such as firewalls and passwords. ensures that the devices on a network are working properly

Systems Administrator: responsible for the overall management, maintenance, and security of computer systems. This includes tasks such as configuring, managing, and troubleshooting hardware and software, as well as implementing backup and recovery strategies.

Database Administrator: responsible for maintaining, designing and overseeing the database of a computer system, controls the access permissions for different users on a network

Software Developer: designs and implements application programs for an organization based on the codes they receive from the programmer

Web Developer: designs a company’s website based on specifications

Social Media Specialist: creates traction for the organization online by communicating with the public on social media platforms such as Twitter to increase business opportunities`

assess the impact of information and communications technology on select fields.

Economic implications of ICT on Education, Medicine, Business, Law Enforcement and Recreation. 

Impact on Education: 

• Computerised database records save paper and are more efficient to use

• Software specifically designed for schools such as moodle can be used to help kids learn in their own way, facilitates group work

• Children can be taught from all over the world (long distance teaching) and information can be accessed from all over the world 

• However, plagiarism becomes more rampant as students are easily able to copy off of a source

 Impact on Medicine: 

• patient information is easily accessible and is usually stored on expert systems

• Expert system: a system that stores patient history and symptons and uses it to diagnose the patient based on their previous history

• eHealth, people can even go to the doctor online (like in teleoradiology)

• Virtual reality simulations can help doctors in training to practice

• 3D printers can create parts of the body such as bones for people who don’t have them to use

• Scans such as MRI and CT scans 

Disadvantages:

• so much misinformation is on the internet, someone can easily self diagnose

Impact on Business in terms of: 

• There are automated stock control systems so that supermarkets can keep track of their product amount

• Computers can be used to distribute advertisements to increase business 

• EPOS means that people can embrace a cashless society, which is much easier for most

• E-commerce means people don’t have to leave the safety of their homes to conduct business, which results in more business

• ATMs are a thing

Impact on Law Enforcement:

• Biometric systems: biometric systems can be used to log criminals, and also act as a security measure by only allowing access to a particular section of a computer system if they have the right credentials

• E-surveillence: people can be watched online with surveillance cameras

Impact on Recreation in terms of: Music and gaming

• Virtual reality which can immerse users in amazing experiences

• CD and DVDs for music and movies

• Movies can make special effects that look real

PART 8 - PROBLEM SOLVING 

outline the steps in problem-solving; 

Steps in problem-solving: 

1. Define the problem

2. Propose and evaluate solutions

3. Determine the best solution

4. Represent solution as an algorithm 

5. Test and validate the algorithm

use the divide-and-conquer approach to decompose large everyday problems into smaller tasks; Basic treatment of the structured approach for solving complex problems. 

define a problem by decomposing it into its significant components; 

When we are decomposing the problem, we often decompose it into three sectors:

• input: what do we want to put into the algorithm? numbers? text?

• output: what do we want to receive from the algorithm? sum? average?

• processing: what kind of processes does the input have to undergo to become output?

And thus, we draw IPO charts.

• IPO CHARTS ARE ALSO CALLED DEFINING DIAGRAMS

An example would be to create an IPO chart to receive the heights of 3 friends and calculate the average.

distinguish between variables and constants

A variable and a constant share the same initial definition: an area or space in memory that holds data that a computer program may manipulate or use. But they also differ in some ways:

• A variable can change throughout the process of an algorithm (e.g. the total)

• A constant remains the same throughout the process of an algorithm (e.g. mathematical constants like PI, birth year)

Data types:

• integer (negative or positive whole numbers)

• real/floating (decimal positive or negative numbers, computer doesn’t work with fractions)

• character (a single character like “A” “B”)

• string (a group of characters, like a word “BOOK”

• boolean (one of two values, yes/no, on/off, etc)

explain the concept of algorithms; Definition of algorithms.

An algorithm is a step by step method that gives a solution. To make things easier, they are often represented in the form of:

• pseudocodes: an algorithm that uses english-like statements and mathematical notation to represent the solution of a problem

• flowcharts: an algorithm that uses the flow of diagrams to represent the solution of a problem

 Characteristics: 

An algorithm must be:

• precise

• unambiguous

• follow the flow of control

• terminate

• finite

represent algorithms in the form of flowchart and pseudocode;

Use of flowchart symbols: 

• input/output: a parallelogram 

• process: a rectangle

• decision: a diamond

• directional arrows: arrows, show the direction of the flowchart

• start/stop: an oval

• preparation: a hexagon, used to declare variables (as real, integer etc)

Pseudocode 

Use of read, input, store, write, print, output, display, 

INPUT: read, store

OUTPUT: write, print, display

conditional branching (if-then, if-then-else, nested conditions); 

IF THEN

Syntax:

IF (condition) then

(action)

EndIf

Notes: 

• pretty straightforward, used mainly to show what happens when something is true

IF-THEN-ELSE

Syntax:

IF (condition) then

(aciton)

Else

(action)

EndIf

Notes:

• still pretty straightforward

NESTED-IF 

Syntax:

If (condition) then

If (condition) then

(action)

Else if (condition) then

(action)

Else 

(action)

EndIf

Else 

(condition)

EndIf

Notes:

• I have no advice for you literally just feel the vibe. I have no idea whats going on

• its basically one big loop sandwich, if you take out the middle you must still have an if then else statement

loops (for, while, repeat). 

FOR LOOP
Syntax:

for counter <- 1 to 10 DO

(action)

Endfor

Note:

• simple enough to follow

WHILE LOOP
Syntax:

while (variable) [relational operator] (value/text) DO

(action)

Endwhile

for example

while num > 10 DO

print “Num is huge”

Endwhile

Note:

• whenever you’re doing a while loop ensure to set it up in a way that the loop continues smoothly

• that is to say, if you have to read a value to begin the loop, you have to read the value again in the loop so it can repeat itself

REPEAT UNTIL LOOP

syntax:

repeat 

(action)

until (variable) = criteria

Notes:

• simple enough, not really used

COMMONLY USED VARIABLES

• total (used to add up numbers in a loop, usually total <- total + num

• count (used to count how many times loop has passed, usually to calculate average, count <- count + 1)

• max (usually set to a low value such as 0, so that over time the highest value becomes max)

• min (usually set to a high value like 9999 so that the lowest value can become min)

Use of relational operators: 

< - less than

> - greater than

= - equal to

<= - less than or equal to

> = - greater than or equal to

< >/== - not equal to

. 

Logical operators: 

AND (^): both criteria must be met

OR (v): either criteria can be met

NOT (~): no criteria can be met 

use of truth tables

Steps

1. Write down what the question is asking you in terms of logical operators (e.g A AND B OR NOT C - (A^B)v~C)

2. Find out how many variables there are, for that amount of variables you’ll need columns for each

3. Start off with the first column being 2 T’s and 2 F’s (two  trues and two false)

4. Fill in the rest of the columns according to the first column. There can be two cases where the first column is true, one where the first and second columns are true, or one where the first is true but the second is false

5. Add columns building onto what the question is asking, so get a column with (A^B) and another with ~C, until you get to the question

6. happy solving!

EXAMPLE OF A TRUTH TABLE

(A^B)~C

Arithmetic operators: 

+  -addition

 – - subtraction

* - multiplication

/ - division

MOD - calculates the remainder when one number is divided by another  - e.g. 7 mod 3 = 2 

syntax: (dividend) mod (divisor)

DIV - calculates the quotient when one number is divided by another

syntax: (dividend) div (divisor)

test algorithms for correctness. 

Desk checks/dry run: the process of manually executing the steps of a pseudocode algorithm without actually running the algorithm on the computer. involves the construction and use of trace tables to verify results. 

Trace tables consist of variable names (identifiers) as column headings and values in the cells, one row for each pass. 

Confusing as hell but we move.

There should be at least two columns, line number and the variable (sometimes multiple) for when they change during an experiment.

During a loop for a trace table, we don’t just keep counting lines, we reset the line number back to the start of the loop

Example of a trace table:

excerpt of a code (lines 4 to 8)

x ← 10

While x > 0

print x

x ← x - 1

ENDWHILE

… And so on and so forth, until the x value is 0.