Also Unit 1

linkers

takes one or more object files made by a compiler and combine them

device driver

allows hardware devices to communicate with a computer’s operating sytem

compiler

turns programming made by humans into machine code which computers can understand

utilities

programs that help manage, maintain, and control computer resources

application software

programs that allow users to do specific tasks, cannot run on its own without systems software

systems software

Important programs that allow hardware to run properly

word processor

produce letters, reports and memos

database

store and retrieve information

graphics manipulation software

software to edit artwork, photos

spreadsheet

used for tasks that involve calculations or graphs and charts

video editing software

produce and edit videos

apps

a computer program that is written and designed for a specific purpose

control software

control devices such as fire alarms and mechanical devices

analogue data

Data which represents physical, constantly varying quantities, such as time, temperature, etc.

digital data

saved in the computer as 0’s and 1’s - this is called binary data. This is sometimes referred to as ‘discreet’ data.

motherboard

also called the system board, is the main printed circut board, can connect to other circuit boards

cpu (central processing unit)

does most of the processing inside a computer

ram (random access memory)

volatile, stores data and applications while they are being used.

rom (read only memory)

non volatile, keeps its contents even when the computer is turned off, memory that has data preinstalled onto it that cannot be removed

secondary (internal/external) storage

another storage device that keeps data when the computer is turned off

graphics card (gpu)

controls the output to a display screen/monitor

sound card

controls output of speakers and headphones

network interface card

allows the computer to communicate with other devices over a computer network

camera

record video and sound

operating systems

provides GUI or CLI, runs and stops applications, organises, saves, and retrieves files, allocates and controls system memory, prevents unauthorised system access, oversees input/output devices for smooth operation

command line interface (CLI)

text based interface

graphical user interface (gui)

often called a ‘WIMP’ interface, input through icons, menus, buttons

desktop computer

computer system designed to be used in a fixed location

laptop computer

portable computer with the same functionality as a desktop

tablet computer

portable computer with a touch screen, mobile operating

measuring software

to capture and log data from sensors

GUI advantages

doesnt require user to learn commands, more user friendly than CLI

GUI disadvantages

uses up more computer memory, limited to icons provided, operating system uses up memory

CLI advantages

not limited to the number of commands, possible to alter computer configuration settings, direct communication with computer allowing for contro and efficiency

CLI disadvantages

user need to learn commands to carry out basic operations, can be error prone, difficult to edit once commands are entered

dialogue based advantages

hands free control, safer to use while operating machinery

dialogue based disadvantages

have to learn commands/keywords, interface need to be trained with voice, not reliable especially with bg noise, complex to program = expensive

gesture based advantages

pointing device not needed, keyboards is not needed, sensor can pick up movement no matter where user is, hygienic as touching screen isnt necessary

gesture based disadvantages

gesture for particular request need to be learnt, a system is required to recognise movements, motion tracking gloves may be required, may become tiring

true gesture based interface

no physical contact with screen

partial gesture based

requires physical contact with screen

desktop computer benefits

spare parts are interchangeable making upgrades and repairs cheaper, can support more powerful software, good power and cooling system, less risk of physical damage as it is stationary, stable internet as it is stationary

desktop drawbacks

lack of portability, transfering files is required when working on different computer, multiple components and wires can lead to clutter

what is software?

programs that control the computer

Hardware

The physical components of a computer system.

Internal Hardware Devices

• Processor (CPU)

• Motherboard

• Random Access Memory (RAM)

• Read Only Memory (ROM)

• Video and Sound Card

• Internal Hard Disk Drive

Motherboard

Central component of any computer system through which every other component communicates. Components are plugged into it directly or indirectly.

Processor (CPU)

The brain of the computer. It controls everything that the computer does and processes the data, moving it in and out of the memory.

Random Access Memory (RAM)

It stores the information currently in use, which is constantly changing.

A fast, volatile memory since when the computer is turned off the data is lost. The more RAM you have the faster your computer works.

Read Only Memory (ROM)

Used to store instructions for the computer to work. The information cant be changed and when the computer is turned off, it wont be lost. The data can be accessed very fast.

Video Card

Allows images to be displayed on the monitor. Along with its installation, software is installed so it tells the computer how to use it.

Sound Card

Allows the computer to produce and input sounds to and from the computer by turning analogue data into digital and vice versa.

Internal Hard Disk Drive

Stores data that is not instantly needed for an indefinite time. It also stores programmes and is used commonly to back up data.

External Hardware

• Inputs

• Outputs

• Peripherals

Input Devices

Used to get data into the computer system. They are manual or automatic.

Output Devices

Used to transfer data out of the computer system. They are temporary or permanent.

Peripheral Devices

Non-essential hardware that connect to the computer externally.

Software

Programmes used for controlling the operation of a computer or processing of electronic data, applications and systems.

Applications Software

Software used in particular situations, which can be used either in general purpose or in one particular situation.

i.e. Word processing, spreadsheet, data manipulation...

Systems Software

Files and programmes that make up a computer.

i.e. Compilers, linkers, device drivers...

Secondary/Backing Storage

Storage devices and media that are not constantly accessible by a computer system.

Operating System

Software program that manages computer resources. They allow components to communicate with each other and enable the computer to run software applications.

They are CLI and GUI.

Command Line Interface (CLI)

The user types in instructions and commands. It is fast but complicated to use. It uses very little RAM. Used in batch processing.

Advantages of CLI

1. User communicates directly with the computer.

2. There's a wide range of commands.

3. Needs very little computer power.

Disadvantages of CLI

1. User must remember complex commands.

2. Lots of typing involved.

3. High chance of errors.

Graphical User Interface (GUI)

The user points at and clicks objects on a screen with a mouse. It is easy to use but needs a large amount of RAM and disk space. It uses Windows, Icons, Menus, and Pointers (WIMP)

Advantages of GUI

1. Quick and easy to enter commands.

2. Less chance of errors.

Disadvantages of GUI

1. Smaller range of commands can be used.

2. Uses more computer power.

Types of Computers

1. Personal Computers

2. Laptops

3. Tablet Computer

4. Smart Phones

Personal Computers

Found in schools, at home or offices. They are made of input, output and storage devices grouped in a base unit.

Standalone PC

They are used by one at a time and can function without being connected to other PCs.

Networked PC

They are connected to other computers in a network in order to share resources and data.

Laptops

Portable computers with LCD screens that are small enough to sit on your lap.

Advantages of PCs compared to a laptop

1. Better components for the same price.

2. Cheaper because components are easier to make.

3. Larger keyboard, easy to use.

4. Design allows heat to escape.

Disadvantages of PCs compared to a laptop

1. Large and bulky, not portable.

2. Need a constant power supply.

3. You cant work with them in different locations and need to copy files to work somewhere else.

Advantages of Laptops over PCs

1. Smaller and lighter, portable.

2. Components use low battery.

3. Rechargeable battery.

4. Usually have built in WiFi to access the internet.

5. No need to transfer files to work with them somewhere el

Disadvantages of laptops to PCs

1. Limited battery life

2. Small keyboard

3. Prone to theft

4. Don’t have a design for heat to escape.

Tablet Computers

Hand held mobile computers that have a touch screen and a few physical buttons. They may come with a SIM card slot to make phone calls and send texts. Normally they have built in sensors like cameras and microphone, and built in WiFi. They are used to access the internet, view multimedia and use apps.

Advantages of Tablets over laptops

1. Smaller and lighter

2. Touchscreen can be used to draw with a stylus.

3. Has built in camera(s)

4. Has longer battery life.

Disadvantages of Tablets compared to Laptops

1. Less storage

2. Not as powerful and slower performance.

3. Keyboard is harder to use because it is smaller.

4. Touch screen is hard to use for detailed tasks.

Smart Phones

They are mobile phones that are able to perform other tasks apart from making phone calls and texting. They have touchscreens or physical built in keyboards and usually have a digital camera, GPS and wireless WiFi and Bluetooth connection.

Advantages of Smart Phones over tablets

1. Smallest of computers, very portable.

2. Some have physical integrated keyboards.

3. Generally cheaper.

4. Practical for making phone calls and texting.

Disadvantages of Smart Phones compared to tablets

1. Very small screen

2. Not as powerful

3. Lower battery life

4. Very small and easy to be misplaced or stolen.

Emerging Technologies

Those currently under development or that will be in 5 to 10 years, which will alter the business and social environment.

1. Artificial Intelligence

2. Biometrics

3. Vision Enhancement

4. Quantum Cryptography

5. Computer-assisted Translation

6. 3D and Holographic Imaging

7. Virtual Reality

8. Robotics.

Artificial Intelligence

Computer science focused on simulating human intelligence with computer systems. Currently used in games, expert systems, languages and robotics.

Impacts of AI on everyday life

1. Accurate prediction of the weather.

2. Increased leisure time.

3. Safer transport due to self parking and autopilot vehicles.

4. Increased personal safety due to alarms.

5. Increased medical care due to robotic surgery assistants.

Biometrics

When unique parts of the body are used as an identification form. They cant be lost, forgotten or stolen; unlike passwords.

Impacts of Biometrics

1. Better airport security with facial recognition and fingerprint scans.

2. Increased security in buildings.

3. Better car security with fingerprint scans to open doors or turn on engines.

4. Better phone security.

Vision Enhancement

Uses video technology projected through the lens of goggles to bring distant objects closer and into focus. It amplifies infrared light so that the image can be seen clearly even in darkness.

Impacts of Vision Enhancement

Militaries worldwide use it to complete missions and carry out surveillance at night.

Robotics

Robots are used to perform physical tasks that could be dangerous to human beings or that are repetitive.

Types of Robots

• Manufacturing Robots

• Carrier Robots

• Domestic Robots

• Exploration Robots

Manufacturing Robots

Perform Manufacturing repetitive tasks more efficiently and rapidly than humans.

Carrier Robots

Carry heavy loads and objects around.

Domestic Robots

Perform domestic chores such as vacuuming.

Exploration Robots

They perform exploration jobs of dangerous or extreme places like Mars.

Impacts of Robotics

1. Increased personal time as robots can do things like your chores for you.

2. More efficient manufacture, as robots work faster and are cheaper than humans.

3. Loss of jobs since many manufacture jobs are replaced by robots.

4. Safer working environment as robots can carry out tasks that are too dangerous for humans.

Quantum Cryptography

Technology that allows messages and data to be sent with complete privacy by encrypting the data using quantum physics methods instead of mathematical. This makes the codes impossible to break through.

Impacts of Quantum Cryptography

1. Completely secure voting that gets rid of the risk of your vote being changed.

2. Completely secure information so your texts cant be read or calls heard.

3. Completely secure bank transfers and personal information.

Computer Assisted Translation

Where a human translator uses computer software to help in the translation process. They are spell checkers, translation memory software and language search engines.