Y8

HT2: Computing Systems

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2a: Recall that a general-purpose computing system is a device for executing programs.
Computing Systems
KeywordDefinition
datafiles and information stored on a computer system
hardwarephysical components that make up a computer system
softwareprograms that run on a computer system
2b: Recall that a program is a sequence of instructions.
Computing Systems
KeywordDefinition
algorithmsequence of instructions to solve a problem
instructioncommand which tells the computer what to do
programsequence of instructions which runs on a computer
sequenceordered list of more than one instruction
2c: Explain the difference between a general-purpose computing system and a purpose-built device.
Computing Systems
KeywordDefinition
embedded computer systemtype of computer which only ever runs one program
general purpose computing systemtype of computer which can execute lots of different programs
purpose built devicetype of machine which has just one purpose
2d: Describe the function of the hardware components used in computing systems.
Computing Systems
KeywordDefinition
inputtype of device which sends data into a computer from the outside world (e.g. mouse)
outputtype of device which receives information from a computer and shares it with the outside world (e.g. printer)
processa calculation which can turn input data into useful information
storagetype of device which saves data so that it can be processed or displayed later
2e: Describe how hardware components work together in order to execute programs.
Computing Systems
KeywordDefinition
CPUCentral Processing Unit which processes data
HDDHard Disk Drive which usually stores more than a solid state drive
Main memoryStores instructions and data whilst a program is running (e.g. RAM)
RAMRandom Access Memory that stores instructions and data for programs currently running
Secondary storageStores instructions and data permanently (e.g. SSD / HDD)
SSDSolid State Drive with no moving parts that is faster than a hard disk drive
2f: Recall that all computing systems, regardless of form, have a similar architecture.
Computing Systems
KeywordDefinition
Computer Architecturethe way the insides of a computer is designed and put together
Computer Systemcombination of hardware and software that is able to process data
CPUcentral processing unit that follows instructions to process data
Databits and bytes that can represent files, images, sound or documents
Form factorwhether a computer is a laptop, tablet, desktop, smartphone or any other shape or size
Hardwarethe physical components that make up a computer system
Instructionsprogram code that tells a computer what to do
Softwarethe programs that run on a computer system
2g: Analyse how hardware components work together in order to execute programs.
Computing Systems
KeywordDefinition
CPUCentral Processing Unit which executes instructions to process data
decodeSecond part of the cycle a processor follows where instructions are understood by the CPU
executeFinal part of the cycle a processor follows where instructions are carried out
fetchFirst part of the cycle a processor follows where instructions are loaded from RAM into the CPU
HDDHard disk drive stores instructions and data for programs which aren't currently running
RAMRandom Access Memory which stores instructions and data for programs which are currently running
ROMRead Only Memory which stores instructions needed when the computer is first switched on
2h: Provide a broad definition of 'operating systems'.
Computing Systems
KeywordDefinition
Androidopen source operating system for tablets and smart phones made by Google
Closed sourcetype of software which you usually have to pay for which you can't add your own bug fixes or features.
iOSclosed source operating system for Apple iPads and iPhones
Linuxopen source operating system often used on web servers or by developers
macOSclosed source operating system for Apple Mac desktops
Open sourcetype of free software which anyone can download or add your own features or bug fixes
Operating Systemsoftware which runs on a computer and allows the user to load apps or manage settings
Windowsclosed source operating system for laptops, tablets and desktops made by Microsoft
2i: Describe the NOT, AND, and OR logical operators.
Computing Systems
KeywordDefinition
ANDLogic operator where the output is only True if both inputs are True
inputvalue that goes into a logic operator
Logic operatorWay of combining True/False values logically (AND, OR or NOT)
NOTLogic operator where the output is the opposite of the input
ORLogic operator where the output is True if either or both inputs are True
outputvalue that comes out as the result of a logic operator
2j: Use logic gates to construct simple logic circuits.
Computing Systems
KeywordDefinition
ANDLogic gate where the output is only On if both inputs are On
inputvalue that goes into a logic gate
Logic gateWay of combining On/Off values logically (AND, OR or NOT)
NOTLogic gate where the output is the opposite of the input
ORLogic gate where the output is On if either or both inputs are On
outputvalue that comes out as the result of a logic gate
2k: Describe how hardware is built out of increasingly complex logic circuits.
Computing Systems
KeywordDefinition
Binary0s and 1s represented by electricity being switched on or off
Logic gatedigital circuitry made up for transistors which can make logical decisions (like AND, NOT, OR)
Processordigital circuitry made up of logic gates which can follow instructions and process data
Transistora digital switch which can be connected together to create logic gates
2l: Recall that data and instructions alike need to be represented using binary digits.
Computing Systems
KeywordDefinition
binarya way of representing data by using 0s and 1s
bita single binary digit (0 or 1)
byte8 bits
datasound, video, text, animation or any other type of file which is stored digitally on a computer
instructionsprogram code which tells a computer what to do
nibble4 bits
2m: Provide a broad definition of 'artificial intelligence'
Computing Systems
KeywordDefinition
artificial intelligencea type of behaviour of a computer which seems to be able to think for itself
chatbotsoftware which a human can have a conversation with
machine learningtype of AI where a computer can learn from its mistakes
natural language processingteaching computers how to understand human speech
turing testif a computer or robot with AI can pass this test the humans won't be able to tell if they're talking to another human or a machine
2n: Provide a broad definition of 'machine learning'.
Computing Systems
KeywordDefinition
algorithmstep by step instructions to solve a problem
artificial intelligencea type of behaviour of a computer which seems to be able to think for itself
feedbacka machine learning algorithm needs to know very quickly whether or not it has guessed the answer to a problem correctly so it can learn from its mistakes
machine learningtype of AI where a computer can learn from its mistakes
traininga machine learning algorithm needs to be fed lots of test data so that it can learn from its mistakes
2o: Identify examples of artificial intelligence in the real world.
Computing Systems
KeywordDefinition
artificial intelligencebehaviour of a computer system that appears to think for itself
computer visionexample of AI where computers can be taught to recognise objects from images or video
machine learningexample of AI where computers can learn from experience and mistakes
speech recognitionexample of AI where computers can be taught to recognise words and sentences from recorded sound
2p: Describe the steps involved in training machines to perform tasks.
Computing Systems
KeywordDefinition
Gather datafirst step of training AI is to collect suitable input data that can be used to teach it how to solve a problem
Testingfinal step of training AI is to check if the AI can solve a problem on reliably and accurately on its own
Trainingsecond step of training AI is to feed input data into the AI and teach tell it what the output should be
2q: Associate the use of artificial intelligence with moral dilemmas.
Computing Systems
KeywordDefinition
accuracyan algorithm for recognising blocking terrorist activity on social media might accidently block a police account
biasan algorithm that analyses CCTV footage to spot potential criminal behaviour might unfairly react to people's skin colour or weight
liabilityif someone is injured by a self driving car it might not be clear who is to blame
reliabilityan algorithm that predicts earthquakes might be correct 99% of the time but miss one really huge disaster
2r: Explain the implications of sharing program code.
Computing Systems
KeywordDefinition
bug fixa type of update to a program which doesn't add any new features but corrects mistakes in previous versions
closed sourcea type of software where only one company can access, fix and improve the code which makes a program work (not usually free)
new featurea type of update to a program which makes it do more than it could before
open sourcea type of software where anyone can access, fix and improve the code which makes a program work (usually free)
source codeprogram code which contains instructions for how the program runs
vulnerabilitya security risk within a program that hackers could use to damage or access your computer