A subject area covering computer hardware, computer software, computer science and anything else relating to the use of digital data-processing devices
Data Representation
Bit
A binary digit (0 or 1). Binary numbers use 'base-2', a counting system that only uses the digits 0 and 1 (unlike decimal which uses digits 0 to 9)
Byte
A group of 8 bits. Bytes are the basic unit data storage and data transfer. Larger amounts of data might be measured in kB, MB, GB, TB, PB or EB
Computer Hardware
Central Processor Unit (CPU)
The 'brain' of a computer. The CPU processes data fed into it via the system bus. It follows instructions in computer programs, performs calculation, makes decisions, etc. CPU speed is generally measured in GigaHertz (GHz), measuring the number of processing cycles-per-second each CPU core is capable of: a 5GHz core can perform 5,000,000,000 operations per second!
CPU Core
A processing unit within a CPU. Each core can run in parallel with the others. Modern CPUs will often have over a dozen cores.
Memory (RAM and ROM)
Computer memory is where data and program instructions are stored whilst the computer is running. Random-access memory (RAM) is temporary (volatile), whilst read-only memory (ROM) keeps data even when powered off (non-volatile). BIOS / UEFI settings are usually stored in ROM
A specialist type of data processing unit, focussed on processing data to render graphics on the screen. GPU speed is measured in FLOPS. Modern GPUs can perform at TFLOPS speed
Peripheral
Hardware devices that are not part of the 'core' computer hardware (peripheral means 'around the edge'), such as keyboards, mice, printers, etc.
Bus
A collection of data transfer wires that allow data to be transferred between hardware devices
System Bus
A number of buses that connects the CPU, RAM, ROM, IO, and other systems within a computer. Usually includes a data bus, an address bus, a control bus, and a peripheral bus such as PCIe
Universal Serial Bus (USB)
A serial communication system often used to connect peripheral devices to a computer
Computer Networks
Network
An inter-connected set of devices, linked by cables or wireless links
Internet
A global 'inter-network', consisting of millions of linked networks
Local Area Network (LAN)
A network that connects devices within a limited area (e.g. a home, school or workplace)
Wide Area Network (WAN)
A network that spans multiple sites across a wide geographical area
Telecommunication
Communicating (sharing information) over long distances ('tele' means far)
World-Wide Web (WWW)
A collection of hypertext documents (usually stored as web sites), shared over a network using HTTP or HTTPS
EtherNet
A type of wired network, commonly used in LANs
Network Protocols
Protocol
A set of rules / standards used for communication
Medium Access Control (MAC)
A hardware addressing protocol, providing a unique 48-bit 'MAC' address to hardware devices, of the form: 00-B0-D0-63-C2-26
Transmission Control Protocol (TCP)
A
User Datagram Protocol (UDP)
A
Internet Protocol (IP)
A
Point-to-Point Protocol (PPP)
A
File Transfer Protocol (FTP and SFTP)
A
Domain Name Service (DNS)
A
Voice over IP (VOIP)
A
Computer Programming
Computer Program
A set of instructions that a computer will follow to solve a task
Machine Code
Computer instructions that the CPU can run directly. The instructions are simply binary values that can be read into the CPU
Low-Level Language
Code that the CPU can understand and run (machine code)
High-Level Language
Code that is easy for humans to understand. High-level languages include Python, C#, JavaScript, etc. This code can't be run by the CPU directly, but must first be translated into machine code.
Web Development
WWW
World-Wide Web
HTTP
HyperText Transfer Protocol
HTTPS
HyperText Transfer Protocol Secure (Encrypted)
HTML
Hyper Text Markup Language
CSS
Cascading Style Sheets
PHP
PHP Hypertext Preprocessor (originally 'Personal Home Page')
JS
JavaScript
Web History
Tim Berners-Lee
A computer scientist who worked at CERN, and who created the key technologies that became the World-Wide Web: HTTP and HTML.
CERN
A large science installation in Switzerland, home of the Large Hadron Collider (LHC). The birthplace of the World-Wide Web.
Images and Graphics
Bitmap Image
An image made up of a 2D grid of pixels. Examples of bitmap image files are PNG, JPEG, BMP, GIF
Vector Image
An image drawn from a set of instructions that draw lines, circles, rectangles, etc. Usually saved as SVG files
User Interfaces (UIs)
User Interface (UI)
The system by which a human user can interact with a computer (HCI). Sometimes this is graphical (GUI) and sometimes the user must type commands (CLI).
Graphical User Interface (GUI)
A system for HCI that shows outputs to the user in a graphical format (windows, text, images, charts, etc) and allows input via interactions with graphical elements (buttons, sliders, menus, links, etc). Sometimes GUIs are called WIMP interfaces
Command-Line Interface (CLI)
An HCI system where the user must type in commands to control the computer, and where the output from the system is in the form of text
User Experience (UX)
The overall feeling (good or bad) that is had from interacting with a computer system
Computer Science Topics
Computer Science (CS)
The study of computer systems and how they can be used to process information
Formal Languages
Finite State Automata (FSA)
Systems that
Data Encoding
Finite State Automata (FSA)
Systems that
Cryptography
Complexity and Tractability
Complexity
The amount of time / 'effort' it takes for a problem to be solved
Tractable
A problem that can be solved within a 'reasonable' amount of time
Intractable
A problem that can't be solved within a 'reasonable' amount of time
Travelling-Salesperson Problem (TSP)
A famous, intractable problem
Te Tukanga Hoahoa Whakaaro The Design Process
Te Pō
Empathise & Define
Observe, ask, listen, research, define, focus
Te Wehenga
Ideate
Brainstorm, come up with ideas, create
Te Ao Mārama
Prototype
Create, analyse, choose
Te Whakaata
Reflect / Review
Identify issues, consider impacts, seek feedback
Te Ao Tangata
Test
Re-develop, improve, refine
Te Whakaahua
Iterate
Develop, refine, adjust, improve
Design Terms
Analyse
Break something down into its parts, showing how they relate to each other to make the whole. More...
Brief
Describes the outcome to be developed: the needs of the stakeholder. It should tell the developer what has to be done and why and contain a set of specifications and constraints that define the requirements.
Conceptual Design
A clear indication of the final outcome.
Constraints
Limitations or restrictions on the development of the digital product: resources, time, budget, etc.
Data integrity
Ensuring that data is accurate, valid and consistent.
Enhance
To improve, make more effective.
Evaluation
Determining the success or worth of something
Fitness for Purpose
Judging if an outcome can do the intended job: resolves the issue identified, meets the requirements, etc.
Identify
Give an acceptable name or label. Distinguish between.
Justification
A clear rationale that supports the selection of a tool or technique.
Legibility
A measure of how easy something is to read: a clear typeface, good contrast, etc.
Organisational requirements
Documented policies and procedures or commonly accepted practices of the school.
Plan
To decide on or arrange things in advance.
Presentation
Refers to the look and feel of the document. For example, have the design principles of harmony, alignment, contrast repetition, proximity and balance been applied, is there a system of text hierarchy?
Protocols
A way of carrying out a process.
Purpose
What the digital outcome is trying to achieve. That is, why the document is being produced.
Accessibility
Supporting people with disabilities to access systems and information
Readability
Ease of comprehension of the text.
Specifications
Define what the outcome will look like and how will it function.
Stakeholder
Those who are directly or indirectly impacted by the digital outcome.
Target Audience
The specified group in society for which the digital outcome is designed or to whom the finished document should appeal.
Testing
Conducting an investigation to provide information about the quality of the outcome. For example, does the project function as it should, does it actually work?
Testing Procedures
A documented plan used to test a digital outcome for fitness for purpose and functionality.
User Document
Word processed or electronic document that tells a user how to locate and use a web page, database and so on.