Digital Technology - Unit 1 Notes

Flashcards based on WJEC GCSE Digital Technology Unit 1 Notes.

What is analogue data?

Data represented in a physical way e.g., grooves in a vinyl record, a shadow on a sundial. It is in a constant state of flux and captures each nuance of that which is being measured.

What is digital data?

Data represented as a combination of 1 or 0 numbers, suitable for computers.

What is sampling frequency?

The number of times that the sound level is sampled per second when converting analogue sound to digital data.

What is a typical sampling frequency used on audio CDs?

44,000 times per second (44 kHz).

Name three examples of analogue devices.

Clocks (analogue clock or watch, or sundials), analogue synthesizers, analogue TVs, early computers (The Difference Engine).

What is an Analogue-to-Digital (A/D) converter?

An electronic circuit which converts continuous signals into discrete digital numbers.

What is a Digital-to-Analogue (D/A) converter?

An electronic circuit for converting a digital signal (a binary one normally) into an analogue signal (current, voltage or electrical charge).

What is a sample resolution?

Also called sampling precision or bit depth, it can affect the sample quality. The higher the sample rate and resolution, the larger the resultant sample.

What are raster graphics?

Matrix data structures representing a grid of pixels. They cannot scale up without loss of quality and structures tend to be large in terms of the memory required to store them.

What are vector graphics?

Images that do not store data by pixels, but are instead sets of instructions for drawing a geometric shape. They can be scaled without loss of quality and use less storage space.

What is data compression?

The process of making a file size smaller.

What is lossless compression?

Compression that uses an algorithm that compresses data into a form that may be decompressed at a later time without any loss of data, returning the file to its exact original form.

What is lossy compression?

A technique that compresses the file size by discarding some of the data. The technique aims to reduce the amount of data that needs to be stored.

What are the three main types of data storage?

Magnetic, optical, and solid-state.

What is secondary storage also known as?

Back-up storage.

Give examples of solid state storage media.

USB flash memory sticks and SSD internal drives.

What is cloud storage?

A type of storage where data is transferred and stored on remote storage systems where it is maintained, controlled, and backed up over a network – the Internet usually.

Name the advantages of speech Input.

Speech input is much faster than keyboard input, No need to learn to type, Less risk of repetitive strain injury, Reduces typing mistakes such as spelling/hitting wrong key,Keyboard takes up room on the desk, Users with a disability that prevents typing can use speech input, Hands-free advantages – it is possible to multitask, Users find talking more natural than typing.

Name the disadvantages of speech Input.

Background noise interferes with speech recognition, Users when they have a speech impediment, sore throat, cold or a strong accent will not be understood, Users with a disability that prevents speech would need to find a different method for input, Difficult to keep data input private as people can hear what you are saying, Words that sound the same, such as ‘too’ and ‘two’ may not be recognised.

What is an ISP?

A company that provides an internet connection to businesses and households, usually for a monthly fee.

What does URL stand for?

Uniform Resource Locators

Describe Broadband.

An internet connection method that uses ADSL or SDSL technology which allows data to be transmitted more quickly over traditional phone lines than with voice-band technology (modem).

What is fibre internet?

Fiber internet offers very good data transfer rates, usually between 35Mbps and 300Mbps, and there is no practical limit on the connection length.

What is an operating system?

Software that manages a computer system.

Name features of an Operting system.

Managing peripherals including input and output devices, Spooling, Managing memory,Process control,Security control, Managing back-up space, File compression, Disk defragmentation, Providing a user interface.

What does HCI stand for?

Human Computer Interfaces

What is a Command Line Interface (CLI)?

An entirely text-based interface that allows a user to communicate with a computer system by typing in commands.

What is a Graphical User Interface (GUI)?

A type of interface that allows users to interact with a computer system through graphical icons.

What is a Touch Sensitive Interface (TSI)?

Commands are issued, or data is input, by touching the screen with your finger or a stylus pen.

What is voice driven interface?

Can be used to issue commands to a computer system and enter data into it.

What is program software?

An off-the-shelf software that fulfils a specific purpose and mainly produced to meet the requirements of the three following types of user needs in the areas of communication, creativity and productivity, to complete the tasks relating to Data management, Data handling, Producing visual material, Resource coordination, Calculating figures.

What is Bespoke software?

Software written to achieve a task for an individual or company, sometimes referred to as ‘customised software’ or ‘tailored software.’

What is process control software?

Software which controls the process of feeding back information from various sources in order to control input and output in real time.

What is antivirus software?

A program that can be loaded into the memory when the computer is running. It monitors activity on a computer system for the signs of virus infection.

What is a data backup?

A copy of data that can be used if the original data is lost.

What are the three main types of backup?

Full backup, incremental backup and differential backup.

What is the Grandfather-Father-Son (GFS) methodology?

A methodology where data is backed up generationally.

What is a disaster recovery plan?

Plan in place for any type of system failures and highlights step by step how the business will recover.

State the difference between cloud computing and cloud storage.

Cloud Computing is using data in the cloud and undertaking specific tasks in the cloud to process it. While Cloud Storage allows the user to store data on the Internet on systems such as Google Drive, Dropbox, iCloud, or OneDrive etc.

What is SaaS?

Software as a Service. he majority of SaaS applications are run directly through your web browser, which means that the client does not need to download or install anything.

What is PaaS?

Platform as a Service. A framework for developers which they can build on and use to create customised applications.

What is IaaS?

Infrastructure as a Service. A highly scalable and automated computer tools that business can purchase instead of buying hardware.

State the six parts of System Development Life Cycle.

System Investigation, System Analysis, System Design, System Implementation, System Maintenance, System Evaluation.

Give a few examples of digital communication methods

Emailing, Instant messaging, Blogs, Video conferencing, Social networking websites and apps.

What is meant by B2B Electronic Data Interchange (EDI)?

Businesses use EDI to exchange documents with one another.

What is online shopping also known as?

E-commerce.

Name the different types of electronic signatures

Simple electronic signatures and Enhanced electronic signatures.

State the different ways malware can spread.

Viruses, Worms, Spyware, Trojans, Keyloggers.

What is Social engineering?

Influencing people psychologically to reveal personal or confidential information.

What is phishing?

Deception using a type of social engineering where internet users are directed to a fake website but which looks like an official website to seek to gather personal or confidential information.

What is a 'brute force' attack?

Repeatedly trying combinations of characters in usernames and passwords in order to gain access to a computer system.

What is a Firewall?

Network security system that monitors incoming and outgoing traffic based on pre-determined rules.A firewall can be a software or hardware security system that controls the incoming and outgoing network traffic.

What is encryption?

The process of changing data so that it is in a non-readable format.

What is Cyber resilience?

A company, or other entity’s, ability to prepare for a cyber-attack and to overcome such an attack, continuing to act as normal, and where necessary, to respond to the attack and recover.

List a few cyber resilience measures a company can use to prevent a cyber attack.

Using a boundary firewall and internet gateway, Having secure system configuration, Admin accounts, Audit trails, Account management, Backup copies, Implementing access control including restricted access to valuable data,Implementing malware protection,Having patch management to ensure the latest updates of software are applied to all machines,Ensuring known vulnerabilities are dealt with and the latest version of an application is being used, Implementing staff training to ensure staff are not putting data at risk.

What is a Digital Footprint?

The information we leave online about ourselves.

State the types of a Digital Footprint?

passive digital footprint and active digital footprint.

Describe Lady Ada Lovelace's contribution to Information Technology.

The first computer programmer, the first person to realize computers could do more than just calculate numbers.

Describe James Gosling's contribution to Information Technology.

The person who developed the Java programming language.

Describe Admiral Grace Hopper's contribution to Information Technology.

The person who devised the first commercial electronic computer.

Describe Alan Turing's contribution to Information Technology.

The person who developed computational theory upon which modern computing is based.

Describe Steve Jobs's contribution to Information Technology.

The person who commoditised computing, and developed smartphones and hand-held devices.

Describe Sir Tim Berners-Lee's contribution to Information Technology.

Creator of the World Wide Web.

State the types of Robot.

Industrial Robots and Autonomous Robot.

What is a Autonomous vehicle?

A vehicle which can sense its environment and move safely without much human input, if at all.

What is Virtual Reality (VR)?

The use of computer technology to create a simulated environment via head-mounted displays (HMDs).

What is Augmented Reality (AR)?

A new technology where companies have developed software on a higher scale than ever for mobile phones and proprietary devices in order to allow users to see the real world overlaying additional information onto the scene.

What is Artificial Intelligence (AI)?

The ability for computer systems to simulate a function normally undertaken by people, such as learning and solving simple and complex problems.

What is Machine Learning (ML)?

An AI application that is the process of using mathematical models from data to help computer systems learn without further direct instructions from people.

What is the Internet of Things (IOT)?

The billions of devices across the world which are now connected to the Internet. These devices all collect and share data with each other and data management systems.