Computer Science



Computer Science learners study the principles and practices of computing and gain confidence in computational thinking and programming. They learn to program by writing computer code and they develop their understanding of the main principles of problem-solving using computers. Learners apply their understanding to develop computer-based solutions to problems using algorithms and a high-level programming language. They also develop a range of technical skills, as well as the ability to test effectively and to evaluate computing solutions. This qualification helps learners appreciate current and emerging computing technologies and the benefits of their use. They learn to recognise the ethical issues and potential risks when using computers.


In this course you will study: computational thinking; looking at a problem in terms of representing it on a computer, how can a problem be split down to smaller parts to make it more manageable, how can a problem be converted into an algorithm and then a program to solve the problem, how the data requirements for a problem can be found. How to write computer programs using a high-level programming language. The components that make up a computer system and their function. The ways that computers can communicate through both wired and wireless connections, including networks and across the internet.


IGCSE Computer Science

(Grades A*-G)

Paper 1

Paper 2


75 Marks

1 Hour 45 minutes

60% weighting

Algorithms and Programming

50 Marks

1 Hour 45 minutes

40% weighting


  • If you take an IGCSE in Computer Science and then go on to study Computer Science at IB or university, you’ll have an advantage over fellow students who are picking up the subject at these higher levels.
  • The increasing importance of information technologies means there is already a growing demand for professionals who are qualified in this field. This IGCSE is very highly regarded and will be useful to you, whatever career you eventually embark upon.
  • Engineering, financial and resource management, multimedia, games design, science and medicine.

Please click on the arrow for a detailed breakdown:

Unit / Block of workKey Episodes / QuestionsAdditional DetailColour CodeLength of time.Possible Symbol?Learner Attribute(s)
Data RepresentationWhy computers use binary to represent all forms of data?
Define the terms bit, nibble, byte, kibibyte, mebibyte, gibibyte, tebibyte, pebibyte and exbibyte
Can you convert positive denary whole numbers (0-255) into 8-bit binary numbers and vice versa?
Can you convert positive denary whole numbers into hexadecimal numbers and vice versa?
Can you convert convert between binary, denary and hexadecimal equivalents of the same number?
Can you add two positive 8-bit binary integers and explain overflow errors which may occur?
Why hexadecimal is used in data representation?
Can you perform logical binary shifts on 8-bit binary integers?
Are you able to perform both left shifts and right shifts?
Can you perform multiple shifts?
What is the effect of performing binary shifts including: ‒Multiplication, Division, Loss of precision?
Can you use two’s complement to represent positive and negative 8-bit integers?
Why use binary codes to represent characters?
What does the term ‘character set’ mean?
Can you explain the relationship between the number of bits per character in a character set, and the number of characters that can be represented using: ASCII, Extended ASCII, Unicode?
Can you explain how sound is sampled and stored in digital form
Are you able to represent a short sound file in binary?
Can you explain how sampling intervals and resolution affect the size of a sound file using the terms: Sample rate, Sample resolution (bit-depth)?
Can you explain the trade-off between file size and the accuracy of the recording?
Can you explain how a bitmap graphic is made up of individual pixels?
Can you explain how each pixel is represented in binary?
How does the colour depth (bits per pixel) determines the number of available colours for an image?
Can you explain how the resolution is the number of pixels in the image
Can you explain the relationship between file size, image resolution and colour depth?
What is the purpose and need for data compression?
Can you explain how compression reduces the size of a file?
Can you explain the impact of compression, including: Less bandwidth required, Less storage space required, Shorter transmission time.
Can you explain how files are compressed using lossy and lossless compression methods?
Can you explain how data can be compressed using run length encoding (RLE) using frequency/data pairs?
Can you explain how reducing resolution, colour depth or sample rate results in data being permanently removed?
Binary systems
Binary shifts and two’s complement
ASCII and Unicode
Representing sound
Representing images
Data compression
 14 Hours Thinker Knowledgeable
Data transmission and encryptionCan you describe the structure of a packet including Packet header (destination address, packet number, originator’s address), Payload and Trailer?
Can you explain the process of packet switching including Packets, routing, routers, packet order and reordering?
How is data transmitted from one device to another using different methods of data transmission including: Serial, Parallel, Simplex, Half-duplex, Full duplex?
Can you explain the suitability of each method for a scenario?
Can you explain the advantages and disadvantages of each method?
Can you describe what the universal serial bus (USB) interface and explain how it is used to transmit data?
What is the need to check for errors after data transmission?
Can you describe each of the following error detection methods?
‒Parity check (odd and even), Checksum, Echo check
Can you describe how check digits are used in data entry including?
‒ISBN, Bar codes
Can you describe how an automatic repeat query (ARQ) is used to establish data is correctly received
What is the need for and purpose of encryption when transmitting data?
Can you explain how data is encrypted using symmetric and asymmetric encryption?
Data packets
Data transmission
Error detection
Check Digit
 8 Hours Knowledgeable
Computer architecture and storageCan you explain the role of the CPU and the fetch-execute cycle?
Can you explain the following registers in the Von Neumann architecture?
‒MAR (Memory Address Register, MDR (Memory Data Register)
‒CIR (Current Instruction Register), Program Counter (PC), Accumulator (ACC)
Can you explain the purpose of common CPU components including?
‒ALU (Arithmetic Logic Unit), CU (Control Unit), Registers”
Can you describe the following terms and how they affect the performance of a CPU?
‒Cores, Cache, Clock
Can you explain the purpose of buses including?
‒The address bus, The data bus, The control bus”
Can you explain the purpose and use of an instruction set for a CPU?
Can you describe what is meant by a microprocessor?
Can you describe the purpose and characteristics of an embedded system?
Can you identify devices which commonly use embedded systems?
Can you explain the meaning of primary storage including the role of?
‒Random Access Memory (RAM), Read Only Memory (ROM)
Can you describe the difference between RAM and ROM and why both are needed?
Can you describe what is meant by virtual memory including?
‒How it is created and used, the reason it is necessary
Whys is the secondary storage needed?
Can you describe the operation of the following types of storage and give examples of each?
‒Magnetic storage, Optical storage, Solid-state storage”
Can you explain what is meant by cloud storage?
Can you explain the advantages and disadvantages of storing data on the cloud in comparison to storing it locally?
CPU architecture
CPU performance and busses
Embedded systems and instruction sets
Secondary storage
Cloud storage
 12 Hours Risk Taker
Inputs and outputsCan you describe what is meant by an input device?
Can you describe each of the following input devices and why they are required?
‒Keyboard, Microphone, Optical mouse, Touch screen (resistive, capacitive and infra-red)
Can you describe each of the following input devices and why they are required?
‒Barcode scanner, QR code scanner, Digital camera, Two-dimensional (2D) and three-dimensional (3D) scanners”
Can you explain the meaning of a sensor?
Can you explain the purpose of the following sensors?
‒Acoustic, Accelerometer, Flow, Gas, Humidity, Infra-red, Level, Light, Magnetic field, Moisture, pH, Pressure, Proximity, Temperature
Can you explain what is meant by an output device?
Can you describe each of the following output devices and why they are required?
‒Speakers, Light emitting diode (LED) screens, Liquid crystal display (LCD) projectors, Liquid crystal display (LCD) screens, Digital light processing (DLP) projectors, Actuators
Can you describe each of the following printing devices and why they are required?
‒Inkjet printer, Laser printer, 3D printer
Manual input devices
Scanners and cameras
Output devices
 10 Hours Knowledgeable
Networks and the InternetCan you explain why a computer needs a network interface card (NIC) to access a network?
Can you describe the role of a router in a network including?
‒The routing of packets, IP address assignment, Connecting local networks to the Internet”
Can you describe what is meant by and the purpose of media access control (MAC) address?
Can you describe the structure of a MAC address?
Can you describe why there are different types of IP addresses?
Can you describe the characteristics and differences between IPv4 and IPv6?
Can you describe that IP address allocation may be static or dynamic?
Can you describe the difference between the Internet and the World Wide Web?
Can you describe how uniform resource locators (URLs) work?
Can you describe the purpose and operation of HTTP and HTTPS in the transmission of web pages?
Can you describe the purpose and functions of a web browser?
Can you describe the use of HTML in displaying web pages?
Can you describe how web pages are located, retrieved, and displayed when a user enters a URL, including the role of?
‒The web browser, IP addresses, The domain name system server (DNS server) and web server, HTML
Can you explain what is meant by cookies including?
‒Session cookies, Persistent cookies”
Can you describe the processes involved in, and the aim of carrying out, a range of cyber security threats including?
‒Brute-force attack, Data interception, Distributed denial of service (DDoS) attack, Hacking, Malware (virus, worm, Trojan horse, spyware, adware, ransomware), Pharming, Phishing and social engineering”
Can you explain how a range of solutions are used to help keep data safe from security threats, including:
‒Access levels, Anti-malware, anti-virus, anti-spyware, Authentication, Automatic software updates, Checking the spelling and tone of communications, Checking the URL attached to a link, Firewalls and proxy servers, Privacy settings, Secure socket layer (SSL) security protocol”
Can you describe the concept of a digital currency and how digital currencies are used?
Can you describe the process of blockchain and how it is used to track digital currency transactions?
Network hardware
MAC and IP addresses
The Internet and web
Web technologies and cookies
Cyber security threats
Cyber security solutions
Digital currency
 14 Hours Inquirer
SoftwareCan you explain the difference between system software and application software?
Can you explain the role of the operating system and utility software as system software?
Can you explain the role and basic functions of an operating system including: Managing files, Providing an interface, Managing peripherals and drivers, Managing memory, Managing multitasking, Providing a platform for running applications, Providing system security, Managing user accounts?
Can you explain how hardware, firmware and an operating system are required to run applications software?
Can you explain how hardware, firmware and an operating system are required to run applications?
Can you describe the role and operation of interrupts including?
‒ How an interrupt is generated, How it is handled using an interrupt service routine, What happens as a result of the interrupts?
Are you able to describe examples of software and hardware interrupts?
Can you explain the meaning of high-level and low-level languages?
Can you explain the advantages and disadvantages of each type?
Can you explain that assembly language is a form of low-level language?
Can you explain the operation of compilers and interpreters?
Can you explain the advantages and disadvantages of compilers and interpreters”
Can you explain the role of an IDE in writing program code and the common functions IDEs provide including?
‒ Code editors, Run-time environment, Translators, Error diagnostics, Auto-completion, Auto-correction, Prettyprint”
Types of software
Operating systems
Languages and translators
 10 Hours Inquirer


Unit / Block of workKey Episodes / QuestionsAdditional DetailColour CodeLength of time.Possible Symbol?Learner Attribute(s)
Chapter 11 – File Management What is a generic file                                                                                                                                                                                                                                                                             Can you manage files effectively ?                                                                                                                                                                                                                                         How can we reduce file size for storage and transmission• identify different file types and their use(s), for example: css, csv, gif, htm, jpg, pdf, png, rtf, txt, zip  2 HOURS  Principled
Chapter 12 -Images Can you identify which Software tools are used to edit an image?                                                                                                                                                                              Can yoy edit an image in an exsisting document?• use software tools to place and edit an image to meet the requirements of its intended application and audience 2 HOURS  Caring 
Chapter 13 – Layout Can you create a Basic doucment for a specific audience?                                                                                                                                                                                    Can you place objects in an document ?                                                                                                                                                                                                                            Can add headers and footers ?use software tools to prepare a basic document to match the purpose and target audience – create a new document or, where appropriate, open an existing document – enter text and numbers – use editing techniques to manipulate text and numbers, including: highlight, delete, move, cut, copy, paste, drag and drop  2 HOURS  Thinker 
Chapter 14 – Styles Can you Compare house styles                                                                                                                                                                                                                                  How do we create style in an exsisting document?understand the purpose of a corporate house style and ensure that all work produced matches this – produce documents which conform to a corporate house style – explain what is meant by corporate branding/house style  2 HOURS  Integrity 
Chapter 15 – Proofing Which Software tools are used to proof read your document?                                                                                                                                                                          How many different proofing techniques are there?use software tools to ensure that all work produced contains as few errors as possible – explain why the automated suggestions given by spell check software do not always give the correct response – use automated tools, including spell check facilities, to remove errors – use validation routines to minimise errors – explain why validation checks must be appropriate to the data that is being checked 2 hours  Caring 
Chapter 16 – Graphs & Charts What are the different Chart types  ?                                                                                                                                                                                                                           Can you create and label charts with secondary axes?produce a graph or chart from the given data – select data to produce a graph/chart, including: using contiguous data, non-contiguous data, and specified data ranges, where necessary – select the graph or chart type to match the required purpose and meet the needs of the audience – label the graph or chart. 2 HOURS  Knowledgable 
Chapter 17 – Document Production Can you Format Text and organise page layout ?                                                                                                                                                                                                    How do we edit a table ?                                                                   What is the purpose of mail merge?format text and organise page layout – set page size – set page orientation – set page and gutter margins – set the number of columns – set the column width and spacing between columns – define the terms widow and orphan – explain why it is necessary to use page, section and column breaks, to adjust pagination and to avoid widows and orphans – set and remove page,. 6 houirs Risk Taker 
Chapter 18 -Data Manipultion Can you create a database?                                                                                                                                                                                                                                                                 Can you manipulate data and present in a form and report?design and use suitable software tools to create an appropriate database record structure – define the terms flat file database and relational database – explain where it would be appropriate  3 weeks  
Chapter 19 – Presentations What is a presentation                                                                    Can you open a source file?                                                            Can you use a master slide to place objects?                           Can you create a presententation?use a master slide to appropriately place objects and set suitable styles to meet the needs of the audience
– identify the need for consistency of presentation, in terms of styles, point sizes, colour schemes,
transitions and animations

 1 week Communicater 
Chapter 20 – Data analysis What is a data model ?                                                                                    Can you create a data model?                                                       How do we manipulate data?                                                       When do we test the data model.                                              How is the data presented ?                                                 create and edit a data model
– define the terms: cells, rows, columns, sheets, tabs, pages, charts
– explain the importance of accurate data entry in spreadsheets
– enter data with 100 per cent accuracy
 4 weeks  Risk Taker 
Unit 21 Website authoring What are Web Development layers ?                                              Can create a webpage  ?                                                                 How do we use stylesheets?                                                               Can you test and publish a website?identify and describe the three web development layers • understand the function of: content layer to enter the content and create the structure of a web page; presentation layer to display and format elements within a web page; behaviour layer to enter scripting language to elements within a web page 4 weeks  integrity 
• use software tools to create the content layer of a web page to meet the needs of the audience – explain the purpose of the head and body sections of a web page – place appropriate elements in the head section of a web page, including: page title, attached stylesheets – place appropriate elements in the body section of a web page – explain why tables are used to structure elements within a web page – insert a table, including: table header, table rows, table data – use appropriate table attributes, including: to adjust cells to span more than one row/column, to set table and cell sizes in terms of pixels and/or % values, to apply styles to tables, to meet the needs of the audience • use software tools to appropriately place the content in a web page – insert appropriate objects into a web page including: text, still images, moving images, sound clips – apply styles to text within a web page – apply styles to a list, including: ordered list, unordered list – insert an appropriate image into a web page – use appropriate image attributes, including: to adjust its size, aspect ratio and alternate text
use software tools to create the presentation layer of a web page – explain what is meant by the term cascading stylesheets – explain the difference between attached stylesheets and inline style attributes – explain the hierarchy of multiple attached stylesheets and inline styles within a web page – explain the difference between a style and a class – create generic external styles and inline style attributes, including: background properties (e.g. colour, images), font properties (e.g. style, typeface), table properties (e.g. background colour, horizontal and vertical alignment, spacing, padding, borders: including collapsed, border thickness, visible/invisible) – create external styles to be tagged in a web page including: h1, h2, h3, p, li, as required – specify the font appearance for each style, including features such as: font family, size, colour, alignment, bold and italic – save styles in cascading stylesheet format – explain why relative file paths must be used for attached stylesheets – attach an external stylesheet to a web page using a relative file path – attach comments to an external stylesheet
know how to publish a website – explain how to upload and publish the content of a website using ftp – test that web page elements work – test navigation within/from a web page using a test plan • test a website – create a test plan to test a website including: web page elements are visible, navigation within/from a web page – justify the choice of test plan
Unit / Block of workKey Episodes / QuestionsAdditional DetailColur CodeLength of time.Possible Symbol?Learner Attribute(s)
TechnologiesCan you explain how sensors, microprocessors and actuators can be used in collaboration to create automated systems?
Can you explain the advantages and disadvantages of an automated system for a given scenario including: Industry, Transport, Agriculture, Weather, Gaming, Lighting, Science?
Can you explain what robots are?
Can you explain the characteristics of robots?
Can you explain the roles that robots perform along with their advantages and disadvantages?
Can you explain the roles of robots in the following areas: Industry, Transport, Agriculture, Medicine, Domestic, Entertainment?
Can you explain what is meant by artificial intelligence (AI)?
Can you explain the main characteristics of AI including: The collection of data and rules, The ability to reason, The ability to learn and adapt?
Can you explain the basic operation and components of AI systems to simulate intelligent behaviour including: Expert systems, Machine learning?
Automated systems
Artificial intelligence
 6 hours Knowledge
Algorithm designCan you explain the program development life cycle?
‒Analysis – including abstraction, decomposition, problem identification requirements
‒Design – including decomposition, structure diagrams, flowcharts and pseudocode
‒Coding – writing program code and iterative testing
‒Testing – testing program code with test data”
Can you explain how flowcharts are used to solve problems?
Can you describe and use flowchart symbols including?
‒Processes, subroutines, input/output, decisions, terminators
Can you create, interpret, correct, complete and amend algorithms using flowcharts?
Can you write algorithms in pseudocode involving sequence, selection and iteration?
Can you state the purpose of an algorithm and be able to describe the processes involved in it?
Can you explain standard methods of solution including?
‒ Linear search, Bubble sort, Totalling, Counting
‒ Finding maximum, minimum and average values
Can you explain the purpose of a given algorithm including?
‒ Stating the purpose of an algorithm
‒ Describing the processes involved in an algorithm”
Can you explain the need for validation checks and be able to write algorithms to implement each validation check including?
‒ Range check, Length check, Type check, Presence check, Format check, Check digit”
Can you identify errors in algorithms and suggest ways to fix the errors?
Can you explain and apply suitable test data including?
‒ Normal, Abnormal, Extreme (largest/smallest acceptable value)
‒ Boundary (largest/smallest acceptable value and corresponding smallest/largest rejected value)
Are you able to complete a trace table for a dry run of an algorithm including variables, outputs and user prompts?
Development life cycle
Algorithms and flowcharts
Algorithms and pseudocode
Standard algorithms
Validation and verification
Testing and trace tables
Creating and refining algorithms
 28 hours Thinker
Programming conceptsCan you use data types: integer, real, char, string and Boolean?
Can you declare and use constants and variables?
Can you use input, output and assignment statements?
Can you use arithmetic operators including MOD and DIV?
Can you use string handling functions?
Can you use selection and nested selection statements?
‒ IF statements, CASE statements
Can you use NOT, AND and OR when creating
Boolean expressions
Can you use of logical operators?
Can you explain the concept of iteration?
‒ Count-controlled loops (FOR loops)
‒ Pre-condition loops (WHILE loops)
‒ Post-condition loops (REPEAT…UNTIL… loops)
Can you write algorithms in pseudo-code involving sequence, selection and iteration?
Can you describe and use one- and two-dimensional arrays in the design of solutions to simple problems
Can you describe and use library routines including?
Data types and operations
Sequence and selection
Library routines
 15 hours Thinker
 Risk Taker
Advanced programming and DatabasesCan you describe the concept of procedures and functions?
Can you write simple procedures and functions?
Can you use parameters to pass data to procedures and functions?
Can you describe that procedures and functions may use local variables which are accessible only within them?
Can you use local variables and explain why it is good practice to do so?
Can you describe the purpose of storing data in a file to be used by a program?
Can you Open, close and use a file for reading and writing including?
‒ Read and write single items of data
‒ Read and write a line of text”
Can you construct truth tables for the following logic gates?
Can you create logic circuits from problem statements, logic expressions or truth tables?
‒ Complete truth tables from problem statements, logic expressions or logic circuit
‒ Write logic expressions from problem statements, logic circuits or truth tables”
Can you explain how to create maintainable programs including the appropriate use of:
‒ Meaningful identifiers, Comments, Procedures and functions
‒ Relevant and appropriate commenting of syntax
Can you use meaningful identifiers for?
‒ Variables and constants, Arrays, Procedures and functions”
Are you able to create a single-table database including?
‒ Fields, Records and Validation
Can you suggest suitable data types for fields, including?
‒ Text/Alphanumeric, Boolean, Character, Integer and Real, Date/Time
Can you describe the purpose of primary keys?
Can you use Read, understand and complete SQL including?
Procedures and functions
File handling
Boolean logic
Maintainable programs
Databases and SQL
 18 hours Thinker
 Risk Taker


Unit / Block of workKey Episodes / QuestionsAdditional DetailColur CodeLength of time.Possible Symbol?Learner Attribute(s)
Chapter 1 Types of Components of a computer system Can you explain the difference between Hardware & Software ?           What are the main components of a computer system?                               Can you identify the role of an operating system?                                    How many types of computers are there?                                                  How has ICT developed over the recent years?Define hardware, giving examples,
Define software, giving examples, Describe the difference between hardware and software
 5 weeks Thinkers
Chapter 2 Input & Output Devices Can you identify Input devices & their uses ?                                                   how is direct data entry recorded and on which devices?                             Can you identify output devices and their uses?
Identify the following input devices:
Keyboards, Numeric Keypads, Pointing Devices (including mouse, touch pad and tracker ball), Remote Controls, Joysticks, Touch Screens, Magnetic Stripe Readers, Chip Readers, PIN Pads, Scanners, Digital Cameras, Microphones, Sensors, Graphics Tablet, MICR, OMR, OCR, Barcode Readers, Video Cameras, Web Cams, Light Pens.
 3 weeks Communicaters 
Chapter 3 – Storage devices and media How does backing of data take place?                                                            Can you identify the types of access?                                                          What is a secondary storage media?Describe the following common backing storage media and their associated devices:
Fixed hard discs, Portable hard discs, Magnetic tapes, Optical backing storage media such as CDs and DVDs, CD ROM/DVD ROM, CD R/DVD R,
CD RW/DVD RW, DVD RAM, Blu-ray, Solid state backing storage, Memory sticks/Pen drives, Flash memory cards
 3 weeks Risk Takers 
Chapter 4 – networks and the effects of using them Can you identify the different types of Networks ?                                   What network issues can take place while communicating?                                                What are modem?                                                                                                                                                                                                                                                                                                                                    What is the difference between IP & mac address ?                                                                                                                                                                                                                                                                      How do computer use wifi on bluetooth to connect to networks.? 2 Weeks  Inquirer
Chapter 5 – The Effects of using ICT What are the effects of using ICT on Employment?                                         How has ICT effected work patterns?                                                          Which type of devices are microproccessor controlled ?                             What are the potential health problems related to the prolonged use of ICT equiment? Explain what is meant by software copyright                                                                                                                                                                Describe the effects of information and communication technology on patterns of employment, including areas of work where there is increased unemployment?                                                                                                                                                                                                            Describe the effects of microprocessor-controlled devices in the home, including their effects on leisure time, social interaction and the need to leave the home?                                                                                                                                                                                          4 weeks Thinker 
Chapter  6 – ICT Applications How many types of ICT applications can you identify?                                 How does a school managment system use ICT?                                            How are computers used in medicine and retail industry?                                               What are the different types monitoring and tracking systems?                   Can you identify the difference between GPS and GIS?                                              Define EFT ?                                                                                                                                                                                                                                                                                                                                     How many differnt types of booking system are there?                                                                                                                                                                                                                                                How are computers used in the libarary?                                                                                                                                                                                                                                                                                What is meant by biometric? 8 weeks Risk Takers 
Chapter 7 -Systems Life Cycle How many types of analysis techniques are there?                                 When does a product go in design phase?                                                 How is product developed and tested?                                                             Can you explain the implementation process?                                             which documents needed to be pesented?                                                  How is the evaluation carried out?                                        What are the analysis techniques?                                                                                                                                                                                                                                                                                             When would a questionnaire be used?                                                                                                                                                                                                                                                                              What is the difference direct change over and parallel? 3 weeks Communicaters 
Chapter 8 – Audiences How have you kept the audience in mind in your design?                                   What is meant by Legal , Moral , Ethical and cultural appreciation?            What do you need to think about when communiating from email?  How can we make sure the interenet is used effectively?Which type of language & Colour should be use?                                                                                                                                                                                                                                                                           What are the Copywright laws?                                                                                                                                                                                                                                                                                                 How can we make sure that an email has privacy protection? 2 Weeks