Source: https://senecalearning.com/en-gb/revision-notes/igcse/computer-science/edexcel-igcse/4-2-2-types-of-computer-systems [Revision notes](https://senecalearning.com/en-gb/revision-notes.md) › [IGCSE](https://senecalearning.com/en-gb/revision-notes/igcse.md) › [Computer Science](https://senecalearning.com/en-gb/revision-notes/igcse/computer-science.md) › [Edexcel IGCSE](https://senecalearning.com/en-gb/revision-notes/igcse/computer-science/edexcel-igcse.md) › Types of Computer Systems # Types of Computer Systems Computer Science: Edexcel IGCSE, topic 4.2.2 ## Types of Computer System There are lots of different types of computer systems, including: ### General purpose systems ![General purpose systems](https://image-v2.cdn.app.senecalearning.com/2018-03/6b1555d1-32f7-4034-b912-8e225967903e/shutterstock_337921478.jpg) - General purpose systems are capable of performing many different tasks. - For example: - PCs - Macs - Smartphones ### Embedded systems ![Embedded systems](https://image-v2.cdn.app.senecalearning.com/courseImages/physics/4.3.4%20Electric%20Safety/washing-machine-2668472_640-min.jpg) - An embedded system is a computer system which is built into another device to support its operation. - For example: - Washing machines. - Digital cameras. - Sat-Navs. ## Test yourself on Types of Computer Systems - A client has asked you to develop a self-checkout machine for his small supermarket which allows customers to scan their shopping and pay for it without him having to oversee the process. What type of computer system would you be developing? [Practise this topic for free](https://app.senecalearning.com/classroom/course/40426d0e-f017-490c-a2b3-c98a77d973bd/section/a1f8840d-8441-47ee-b2b3-903205acdb01/session) - Previous topic: [4.2.1 Elements of Computer Systems](https://senecalearning.com/en-gb/revision-notes/igcse/computer-science/edexcel-igcse/4-2-1-elements-of-computer-systems.md) - Next topic: [4.2.3 Memory - RAM](https://senecalearning.com/en-gb/revision-notes/igcse/computer-science/edexcel-igcse/4-2-3-memory-ram.md) ## Computer Science: Edexcel IGCSE contents ### 1 Problem Solving - 1.1 Algorithms - [1.1.1 Algorithm Thinking](https://senecalearning.com/en-gb/revision-notes/igcse/computer-science/edexcel-igcse/1-1-1-algorithm-thinking.md) - [1.1.2 Interpreting Algorithms](https://senecalearning.com/en-gb/revision-notes/igcse/computer-science/edexcel-igcse/1-1-2-interpreting-algorithms.md) - [1.1.3 Expressing Algorithms - Pseudocode](https://senecalearning.com/en-gb/revision-notes/igcse/computer-science/edexcel-igcse/1-1-3-expressing-algorithms-pseudocode.md) - [1.1.4 Expressing Algorithms - Flow Charts](https://senecalearning.com/en-gb/revision-notes/igcse/computer-science/edexcel-igcse/1-1-4-expressing-algorithms-flow-charts.md) - [1.1.5 Correcting Algorithms](https://senecalearning.com/en-gb/revision-notes/igcse/computer-science/edexcel-igcse/1-1-5-correcting-algorithms.md) - [1.1.6 Completing Algorithms](https://senecalearning.com/en-gb/revision-notes/igcse/computer-science/edexcel-igcse/1-1-6-completing-algorithms.md) - [1.1.7 Search Algorithms](https://senecalearning.com/en-gb/revision-notes/igcse/computer-science/edexcel-igcse/1-1-7-search-algorithms.md) - [1.1.8 Linear Search](https://senecalearning.com/en-gb/revision-notes/igcse/computer-science/edexcel-igcse/1-1-8-linear-search.md) - [1.1.9 Binary Search](https://senecalearning.com/en-gb/revision-notes/igcse/computer-science/edexcel-igcse/1-1-9-binary-search.md) - [1.1.10 Sort Algorithms](https://senecalearning.com/en-gb/revision-notes/igcse/computer-science/edexcel-igcse/1-1-10-sort-algorithms.md) - [1.1.11 Bubble Sort](https://senecalearning.com/en-gb/revision-notes/igcse/computer-science/edexcel-igcse/1-1-11-bubble-sort.md) - [1.1.12 Merge Sort](https://senecalearning.com/en-gb/revision-notes/igcse/computer-science/edexcel-igcse/1-1-12-merge-sort.md) - 1.2 Decomposition & Abstraction - [1.2.1 Computational Thinking - Abstraction](https://senecalearning.com/en-gb/revision-notes/igcse/computer-science/edexcel-igcse/1-2-1-computational-thinking-abstraction.md) - [1.2.2 Computational Thinking - Decomposition](https://senecalearning.com/en-gb/revision-notes/igcse/computer-science/edexcel-igcse/1-2-2-computational-thinking-decomposition.md) - [1.2.3 End of Topic Test - Algorithms](https://senecalearning.com/en-gb/revision-notes/igcse/computer-science/edexcel-igcse/1-2-3-end-of-topic-test-algorithms.md) ### 2 Programming - 2.1 Develop Code - [2.1.1 Maintainability](https://senecalearning.com/en-gb/revision-notes/igcse/computer-science/edexcel-igcse/2-1-1-maintainability.md) - [2.1.2 Comments](https://senecalearning.com/en-gb/revision-notes/igcse/computer-science/edexcel-igcse/2-1-2-comments.md) - [2.1.3 Exceptions](https://senecalearning.com/en-gb/revision-notes/igcse/computer-science/edexcel-igcse/2-1-3-exceptions.md) - [2.1.4 Syntax Error](https://senecalearning.com/en-gb/revision-notes/igcse/computer-science/edexcel-igcse/2-1-4-syntax-error.md) - [2.1.5 Logic Error](https://senecalearning.com/en-gb/revision-notes/igcse/computer-science/edexcel-igcse/2-1-5-logic-error.md) - [2.1.6 Runtime Error](https://senecalearning.com/en-gb/revision-notes/igcse/computer-science/edexcel-igcse/2-1-6-runtime-error.md) - [2.1.7 Purpose of Testing](https://senecalearning.com/en-gb/revision-notes/igcse/computer-science/edexcel-igcse/2-1-7-purpose-of-testing.md) - [2.1.8 Test Plans](https://senecalearning.com/en-gb/revision-notes/igcse/computer-science/edexcel-igcse/2-1-8-test-plans.md) - 2.2 Constructs - [2.2.1 Selection](https://senecalearning.com/en-gb/revision-notes/igcse/computer-science/edexcel-igcse/2-2-1-selection.md) - [2.2.2 Sequence](https://senecalearning.com/en-gb/revision-notes/igcse/computer-science/edexcel-igcse/2-2-2-sequence.md) - [2.2.3 Iteration](https://senecalearning.com/en-gb/revision-notes/igcse/computer-science/edexcel-igcse/2-2-3-iteration.md) - 2.3 Data Types & Structures - [2.3.1 Variables & Constants](https://senecalearning.com/en-gb/revision-notes/igcse/computer-science/edexcel-igcse/2-3-1-variables-and-constants.md) - [2.3.2 Scope](https://senecalearning.com/en-gb/revision-notes/igcse/computer-science/edexcel-igcse/2-3-2-scope.md) - [2.3.3 Data Types](https://senecalearning.com/en-gb/revision-notes/igcse/computer-science/edexcel-igcse/2-3-3-data-types.md) - [2.3.4 Casting](https://senecalearning.com/en-gb/revision-notes/igcse/computer-science/edexcel-igcse/2-3-4-casting.md) - [2.3.5 Data Structures - Arrays](https://senecalearning.com/en-gb/revision-notes/igcse/computer-science/edexcel-igcse/2-3-5-data-structures-arrays.md) - [2.3.6 Data Structures - 2D Arrays](https://senecalearning.com/en-gb/revision-notes/igcse/computer-science/edexcel-igcse/2-3-6-data-structures-2d-arrays.md) - [2.3.7 Data Structures - Strings](https://senecalearning.com/en-gb/revision-notes/igcse/computer-science/edexcel-igcse/2-3-7-data-structures-strings.md) - [2.3.8 Data Structures - Records](https://senecalearning.com/en-gb/revision-notes/igcse/computer-science/edexcel-igcse/2-3-8-data-structures-records.md) - 2.4 Input / Output - [2.4.1 Input and Output](https://senecalearning.com/en-gb/revision-notes/igcse/computer-science/edexcel-igcse/2-4-1-input-and-output.md) - [2.4.2 Validation and Sanitation](https://senecalearning.com/en-gb/revision-notes/igcse/computer-science/edexcel-igcse/2-4-2-validation-and-sanitation.md) - [2.4.3 Files](https://senecalearning.com/en-gb/revision-notes/igcse/computer-science/edexcel-igcse/2-4-3-files.md) - [2.4.4 File Handling](https://senecalearning.com/en-gb/revision-notes/igcse/computer-science/edexcel-igcse/2-4-4-file-handling.md) - 2.5 Operators - [2.5.1 Arithmetic Operators](https://senecalearning.com/en-gb/revision-notes/igcse/computer-science/edexcel-igcse/2-5-1-arithmetic-operators.md) - [2.5.2 Relational Operators](https://senecalearning.com/en-gb/revision-notes/igcse/computer-science/edexcel-igcse/2-5-2-relational-operators.md) - [2.5.3 Boolean Operators](https://senecalearning.com/en-gb/revision-notes/igcse/computer-science/edexcel-igcse/2-5-3-boolean-operators.md) - 2.6 Subprograms - [2.6.1 Modularity](https://senecalearning.com/en-gb/revision-notes/igcse/computer-science/edexcel-igcse/2-6-1-modularity.md) - [2.6.2 End of Topic Test - Programming](https://senecalearning.com/en-gb/revision-notes/igcse/computer-science/edexcel-igcse/2-6-2-end-of-topic-test-programming.md) ### 3 Data - 3.1 Binary - [3.1.1 Number Bases](https://senecalearning.com/en-gb/revision-notes/igcse/computer-science/edexcel-igcse/3-1-1-number-bases.md) - [3.1.2 Negative Binary Numbers](https://senecalearning.com/en-gb/revision-notes/igcse/computer-science/edexcel-igcse/3-1-2-negative-binary-numbers.md) - [3.1.3 Binary Addition](https://senecalearning.com/en-gb/revision-notes/igcse/computer-science/edexcel-igcse/3-1-3-binary-addition.md) - [3.1.4 Binary Shifts](https://senecalearning.com/en-gb/revision-notes/igcse/computer-science/edexcel-igcse/3-1-4-binary-shifts.md) - 3.2 Data Representation - [3.2.1 Representing Text](https://senecalearning.com/en-gb/revision-notes/igcse/computer-science/edexcel-igcse/3-2-1-representing-text.md) - [3.2.2 ASCII](https://senecalearning.com/en-gb/revision-notes/igcse/computer-science/edexcel-igcse/3-2-2-ascii.md) - [3.2.3 Unicode](https://senecalearning.com/en-gb/revision-notes/igcse/computer-science/edexcel-igcse/3-2-3-unicode.md) - [3.2.4 Representing Images](https://senecalearning.com/en-gb/revision-notes/igcse/computer-science/edexcel-igcse/3-2-4-representing-images.md) - [3.2.5 Representing Sound](https://senecalearning.com/en-gb/revision-notes/igcse/computer-science/edexcel-igcse/3-2-5-representing-sound.md) - 3.3 Data Storage & Compression - [3.3.1 Capacity](https://senecalearning.com/en-gb/revision-notes/igcse/computer-science/edexcel-igcse/3-3-1-capacity.md) - [3.3.2 Calculating Capacity Requirements](https://senecalearning.com/en-gb/revision-notes/igcse/computer-science/edexcel-igcse/3-3-2-calculating-capacity-requirements.md) - [3.3.3 Data Compression](https://senecalearning.com/en-gb/revision-notes/igcse/computer-science/edexcel-igcse/3-3-3-data-compression.md) - [3.3.4 Run Length Encoding](https://senecalearning.com/en-gb/revision-notes/igcse/computer-science/edexcel-igcse/3-3-4-run-length-encoding.md) - 3.4 Encryption - [3.4.1 Encryption](https://senecalearning.com/en-gb/revision-notes/igcse/computer-science/edexcel-igcse/3-4-1-encryption.md) - [3.4.2 Caesar Cipher](https://senecalearning.com/en-gb/revision-notes/igcse/computer-science/edexcel-igcse/3-4-2-caesar-cipher.md) - [3.4.3 Ciphers](https://senecalearning.com/en-gb/revision-notes/igcse/computer-science/edexcel-igcse/3-4-3-ciphers.md) - 3.5 Databases - [3.5.1 Databases](https://senecalearning.com/en-gb/revision-notes/igcse/computer-science/edexcel-igcse/3-5-1-databases.md) - [3.5.2 End of Topic Test - Data & Representation](https://senecalearning.com/en-gb/revision-notes/igcse/computer-science/edexcel-igcse/3-5-2-end-of-topic-test-data-and-representation.md) ### 4 Computers - 4.1 Machines & Computational Modelling - [4.1.1 Computational Models](https://senecalearning.com/en-gb/revision-notes/igcse/computer-science/edexcel-igcse/4-1-1-computational-models.md) - [4.1.2 Input-Process-Output Model](https://senecalearning.com/en-gb/revision-notes/igcse/computer-science/edexcel-igcse/4-1-2-input-process-output-model.md) - 4.2 Hardware - [4.2.1 Elements of Computer Systems](https://senecalearning.com/en-gb/revision-notes/igcse/computer-science/edexcel-igcse/4-2-1-elements-of-computer-systems.md) - [4.2.2 Types of Computer Systems](https://senecalearning.com/en-gb/revision-notes/igcse/computer-science/edexcel-igcse/4-2-2-types-of-computer-systems.md) - [4.2.3 Memory - RAM](https://senecalearning.com/en-gb/revision-notes/igcse/computer-science/edexcel-igcse/4-2-3-memory-ram.md) - [4.2.4 Memory - ROM](https://senecalearning.com/en-gb/revision-notes/igcse/computer-science/edexcel-igcse/4-2-4-memory-rom.md) - [4.2.5 Memory - Cache](https://senecalearning.com/en-gb/revision-notes/igcse/computer-science/edexcel-igcse/4-2-5-memory-cache.md) - [4.2.6 Running Out of Memory](https://senecalearning.com/en-gb/revision-notes/igcse/computer-science/edexcel-igcse/4-2-6-running-out-of-memory.md) - [4.2.7 Virtual Memory](https://senecalearning.com/en-gb/revision-notes/igcse/computer-science/edexcel-igcse/4-2-7-virtual-memory.md) - [4.2.8 Magnetic Storage](https://senecalearning.com/en-gb/revision-notes/igcse/computer-science/edexcel-igcse/4-2-8-magnetic-storage.md) - [4.2.9 Properties of Magnetic Media](https://senecalearning.com/en-gb/revision-notes/igcse/computer-science/edexcel-igcse/4-2-9-properties-of-magnetic-media.md) - [4.2.10 Examples of Magnetic Storage](https://senecalearning.com/en-gb/revision-notes/igcse/computer-science/edexcel-igcse/4-2-10-examples-of-magnetic-storage.md) - [4.2.11 Solid State Storage](https://senecalearning.com/en-gb/revision-notes/igcse/computer-science/edexcel-igcse/4-2-11-solid-state-storage.md) - [4.2.12 Properties of Solid State Media](https://senecalearning.com/en-gb/revision-notes/igcse/computer-science/edexcel-igcse/4-2-12-properties-of-solid-state-media.md) - [4.2.13 Optical Storage](https://senecalearning.com/en-gb/revision-notes/igcse/computer-science/edexcel-igcse/4-2-13-optical-storage.md) - [4.2.14 Properties of Optical Storage](https://senecalearning.com/en-gb/revision-notes/igcse/computer-science/edexcel-igcse/4-2-14-properties-of-optical-storage.md) - [4.2.15 Examples of Optical Storage](https://senecalearning.com/en-gb/revision-notes/igcse/computer-science/edexcel-igcse/4-2-15-examples-of-optical-storage.md) - [4.2.16 Types of Optical Disk](https://senecalearning.com/en-gb/revision-notes/igcse/computer-science/edexcel-igcse/4-2-16-types-of-optical-disk.md) - [4.2.17 Von Neumann Architecture](https://senecalearning.com/en-gb/revision-notes/igcse/computer-science/edexcel-igcse/4-2-17-von-neumann-architecture.md) - [4.2.18 Registers of the Central Processing Unit (CPU)](https://senecalearning.com/en-gb/revision-notes/igcse/computer-science/edexcel-igcse/4-2-18-registers-of-the-central-processing-unit-cpu.md) - [4.2.19 Fetch-Decode-Execute Cycle](https://senecalearning.com/en-gb/revision-notes/igcse/computer-science/edexcel-igcse/4-2-19-fetch-decode-execute-cycle.md) - [4.2.20 Factors Affecting CPU Performance](https://senecalearning.com/en-gb/revision-notes/igcse/computer-science/edexcel-igcse/4-2-20-factors-affecting-cpu-performance.md) - [4.2.21 The Cloud](https://senecalearning.com/en-gb/revision-notes/igcse/computer-science/edexcel-igcse/4-2-21-the-cloud.md) - [4.2.22 How the Cloud Works](https://senecalearning.com/en-gb/revision-notes/igcse/computer-science/edexcel-igcse/4-2-22-how-the-cloud-works.md) - [4.2.23 The Cloud - Pros](https://senecalearning.com/en-gb/revision-notes/igcse/computer-science/edexcel-igcse/4-2-23-the-cloud-pros.md) - [4.2.24 The Cloud - Cons](https://senecalearning.com/en-gb/revision-notes/igcse/computer-science/edexcel-igcse/4-2-24-the-cloud-cons.md) - [4.2.25 End of Topic Test - Hardware](https://senecalearning.com/en-gb/revision-notes/igcse/computer-science/edexcel-igcse/4-2-25-end-of-topic-test-hardware.md) - 4.3 Logic - [4.3.1 Binary Systems](https://senecalearning.com/en-gb/revision-notes/igcse/computer-science/edexcel-igcse/4-3-1-binary-systems.md) - [4.3.2 Logic Circuits](https://senecalearning.com/en-gb/revision-notes/igcse/computer-science/edexcel-igcse/4-3-2-logic-circuits.md) - [4.3.3 Boolean Logic](https://senecalearning.com/en-gb/revision-notes/igcse/computer-science/edexcel-igcse/4-3-3-boolean-logic.md) - [4.3.4 End of Topic Test - Logic](https://senecalearning.com/en-gb/revision-notes/igcse/computer-science/edexcel-igcse/4-3-4-end-of-topic-test-logic.md) - 4.4 Software - [4.4.1 Operating Systems](https://senecalearning.com/en-gb/revision-notes/igcse/computer-science/edexcel-igcse/4-4-1-operating-systems.md) - [4.4.2 User Interface Managetment](https://senecalearning.com/en-gb/revision-notes/igcse/computer-science/edexcel-igcse/4-4-2-user-interface-managetment.md) - [4.4.3 Memory and Process Management](https://senecalearning.com/en-gb/revision-notes/igcse/computer-science/edexcel-igcse/4-4-3-memory-and-process-management.md) - [4.4.4 File Management](https://senecalearning.com/en-gb/revision-notes/igcse/computer-science/edexcel-igcse/4-4-4-file-management.md) - [4.4.5 Device Management](https://senecalearning.com/en-gb/revision-notes/igcse/computer-science/edexcel-igcse/4-4-5-device-management.md) - [4.4.6 User Management](https://senecalearning.com/en-gb/revision-notes/igcse/computer-science/edexcel-igcse/4-4-6-user-management.md) - [4.4.7 Encryption Software](https://senecalearning.com/en-gb/revision-notes/igcse/computer-science/edexcel-igcse/4-4-7-encryption-software.md) - [4.4.8 Defragmentation Software](https://senecalearning.com/en-gb/revision-notes/igcse/computer-science/edexcel-igcse/4-4-8-defragmentation-software.md) - [4.4.9 Data Compression Software](https://senecalearning.com/en-gb/revision-notes/igcse/computer-science/edexcel-igcse/4-4-9-data-compression-software.md) - [4.4.10 Backup Software](https://senecalearning.com/en-gb/revision-notes/igcse/computer-science/edexcel-igcse/4-4-10-backup-software.md) - 4.5 Programming Languages - [4.5.1 High Level Languages](https://senecalearning.com/en-gb/revision-notes/igcse/computer-science/edexcel-igcse/4-5-1-high-level-languages.md) - [4.5.2 Low Level Languages](https://senecalearning.com/en-gb/revision-notes/igcse/computer-science/edexcel-igcse/4-5-2-low-level-languages.md) - [4.5.3 Translators - Compilers](https://senecalearning.com/en-gb/revision-notes/igcse/computer-science/edexcel-igcse/4-5-3-translators-compilers.md) - [4.5.4 Translators - Interpreters](https://senecalearning.com/en-gb/revision-notes/igcse/computer-science/edexcel-igcse/4-5-4-translators-interpreters.md) - [4.5.5 Translators - Assemblers](https://senecalearning.com/en-gb/revision-notes/igcse/computer-science/edexcel-igcse/4-5-5-translators-assemblers.md) - [4.5.6 End of Topic Test - Translation & Representation](https://senecalearning.com/en-gb/revision-notes/igcse/computer-science/edexcel-igcse/4-5-6-end-of-topic-test-translation-and-representation.md) ### 5 Communication & The Internet - 5.1 Networks - [5.1.1 Benefits of Networks](https://senecalearning.com/en-gb/revision-notes/igcse/computer-science/edexcel-igcse/5-1-1-benefits-of-networks.md) - [5.1.2 Network Performance](https://senecalearning.com/en-gb/revision-notes/igcse/computer-science/edexcel-igcse/5-1-2-network-performance.md) - [5.1.3 Types of Network](https://senecalearning.com/en-gb/revision-notes/igcse/computer-science/edexcel-igcse/5-1-3-types-of-network.md) - [5.1.4 Client-Server Model](https://senecalearning.com/en-gb/revision-notes/igcse/computer-science/edexcel-igcse/5-1-4-client-server-model.md) - [5.1.5 Pros of Client-Server Model](https://senecalearning.com/en-gb/revision-notes/igcse/computer-science/edexcel-igcse/5-1-5-pros-of-client-server-model.md) - [5.1.6 Cons of Client-Server Model](https://senecalearning.com/en-gb/revision-notes/igcse/computer-science/edexcel-igcse/5-1-6-cons-of-client-server-model.md) - [5.1.7 Peer-to-Peer Model](https://senecalearning.com/en-gb/revision-notes/igcse/computer-science/edexcel-igcse/5-1-7-peer-to-peer-model.md) - [5.1.8 Pros of Peer-to-Peer Model](https://senecalearning.com/en-gb/revision-notes/igcse/computer-science/edexcel-igcse/5-1-8-pros-of-peer-to-peer-model.md) - [5.1.9 Cons of Peer-to-Peer Model](https://senecalearning.com/en-gb/revision-notes/igcse/computer-science/edexcel-igcse/5-1-9-cons-of-peer-to-peer-model.md) - [5.1.10 Network Hardware](https://senecalearning.com/en-gb/revision-notes/igcse/computer-science/edexcel-igcse/5-1-10-network-hardware.md) - [5.1.11 Transmission Media](https://senecalearning.com/en-gb/revision-notes/igcse/computer-science/edexcel-igcse/5-1-11-transmission-media.md) - [5.1.12 WiFi](https://senecalearning.com/en-gb/revision-notes/igcse/computer-science/edexcel-igcse/5-1-12-wifi.md) - [5.1.13 WiFi Frequency and Channels](https://senecalearning.com/en-gb/revision-notes/igcse/computer-science/edexcel-igcse/5-1-13-wifi-frequency-and-channels.md) - [5.1.14 WiFi Encryption](https://senecalearning.com/en-gb/revision-notes/igcse/computer-science/edexcel-igcse/5-1-14-wifi-encryption.md) - [5.1.15 Network Protocols](https://senecalearning.com/en-gb/revision-notes/igcse/computer-science/edexcel-igcse/5-1-15-network-protocols.md) - [5.1.16 Transmission Protocols](https://senecalearning.com/en-gb/revision-notes/igcse/computer-science/edexcel-igcse/5-1-16-transmission-protocols.md) - [5.1.17 Web Protocols](https://senecalearning.com/en-gb/revision-notes/igcse/computer-science/edexcel-igcse/5-1-17-web-protocols.md) - [5.1.18 Email Protocols](https://senecalearning.com/en-gb/revision-notes/igcse/computer-science/edexcel-igcse/5-1-18-email-protocols.md) - [5.1.19 Layers](https://senecalearning.com/en-gb/revision-notes/igcse/computer-science/edexcel-igcse/5-1-19-layers.md) - [5.1.20 TCP and OSI Models](https://senecalearning.com/en-gb/revision-notes/igcse/computer-science/edexcel-igcse/5-1-20-tcp-and-osi-models.md) - [5.1.21 Advantages of Layering](https://senecalearning.com/en-gb/revision-notes/igcse/computer-science/edexcel-igcse/5-1-21-advantages-of-layering.md) - [5.1.22 Topology - Star](https://senecalearning.com/en-gb/revision-notes/igcse/computer-science/edexcel-igcse/5-1-22-topology-star.md) - [5.1.23 Topology - Mesh](https://senecalearning.com/en-gb/revision-notes/igcse/computer-science/edexcel-igcse/5-1-23-topology-mesh.md) - [5.1.24 Topology - Ring](https://senecalearning.com/en-gb/revision-notes/igcse/computer-science/edexcel-igcse/5-1-24-topology-ring.md) - [5.1.25 Topology - Bus](https://senecalearning.com/en-gb/revision-notes/igcse/computer-science/edexcel-igcse/5-1-25-topology-bus.md) - [5.1.26 End of Topic Test - Networks](https://senecalearning.com/en-gb/revision-notes/igcse/computer-science/edexcel-igcse/5-1-26-end-of-topic-test-networks.md) - 5.2 Network Security - [5.2.1 User Access Levels](https://senecalearning.com/en-gb/revision-notes/igcse/computer-science/edexcel-igcse/5-2-1-user-access-levels.md) - [5.2.2 Encryption](https://senecalearning.com/en-gb/revision-notes/igcse/computer-science/edexcel-igcse/5-2-2-encryption.md) - [5.2.3 Protecting Against Malware](https://senecalearning.com/en-gb/revision-notes/igcse/computer-science/edexcel-igcse/5-2-3-protecting-against-malware.md) - [5.2.4 Firewalls](https://senecalearning.com/en-gb/revision-notes/igcse/computer-science/edexcel-igcse/5-2-4-firewalls.md) - [5.2.5 Forms of Attack](https://senecalearning.com/en-gb/revision-notes/igcse/computer-science/edexcel-igcse/5-2-5-forms-of-attack.md) - [5.2.6 Penetration Testing](https://senecalearning.com/en-gb/revision-notes/igcse/computer-science/edexcel-igcse/5-2-6-penetration-testing.md) - [5.2.7 Malware](https://senecalearning.com/en-gb/revision-notes/igcse/computer-science/edexcel-igcse/5-2-7-malware.md) - [5.2.8 How Malware Spreads](https://senecalearning.com/en-gb/revision-notes/igcse/computer-science/edexcel-igcse/5-2-8-how-malware-spreads.md) - [5.2.9 Social Engineering](https://senecalearning.com/en-gb/revision-notes/igcse/computer-science/edexcel-igcse/5-2-9-social-engineering.md) - [5.2.10 Protecting Against Social Engineering](https://senecalearning.com/en-gb/revision-notes/igcse/computer-science/edexcel-igcse/5-2-10-protecting-against-social-engineering.md) - [5.2.11 Phishing](https://senecalearning.com/en-gb/revision-notes/igcse/computer-science/edexcel-igcse/5-2-11-phishing.md) - [5.2.12 Network Administration](https://senecalearning.com/en-gb/revision-notes/igcse/computer-science/edexcel-igcse/5-2-12-network-administration.md) - [5.2.13 Network Forensics](https://senecalearning.com/en-gb/revision-notes/igcse/computer-science/edexcel-igcse/5-2-13-network-forensics.md) - 5.3 The Internet & the World Wide Web - [5.3.1 IP Addresses](https://senecalearning.com/en-gb/revision-notes/igcse/computer-science/edexcel-igcse/5-3-1-ip-addresses.md) - [5.3.2 Types of IP Address](https://senecalearning.com/en-gb/revision-notes/igcse/computer-science/edexcel-igcse/5-3-2-types-of-ip-address.md) - [5.3.3 MAC Addresses](https://senecalearning.com/en-gb/revision-notes/igcse/computer-science/edexcel-igcse/5-3-3-mac-addresses.md) - [5.3.4 Packet Switching](https://senecalearning.com/en-gb/revision-notes/igcse/computer-science/edexcel-igcse/5-3-4-packet-switching.md) - [5.3.5 How Do Packets Get Routed?](https://senecalearning.com/en-gb/revision-notes/igcse/computer-science/edexcel-igcse/5-3-5-how-do-packets-get-routed.md) - [5.3.6 Did My Data Arrive Safely?](https://senecalearning.com/en-gb/revision-notes/igcse/computer-science/edexcel-igcse/5-3-6-did-my-data-arrive-safely.md) - [5.3.7 The Internet](https://senecalearning.com/en-gb/revision-notes/igcse/computer-science/edexcel-igcse/5-3-7-the-internet.md) - [5.3.8 URLs](https://senecalearning.com/en-gb/revision-notes/igcse/computer-science/edexcel-igcse/5-3-8-urls.md) - [5.3.9 DNS](https://senecalearning.com/en-gb/revision-notes/igcse/computer-science/edexcel-igcse/5-3-9-dns.md) - [5.3.10 Web Hosting](https://senecalearning.com/en-gb/revision-notes/igcse/computer-science/edexcel-igcse/5-3-10-web-hosting.md) - [5.3.11 End of Topic Test - Security](https://senecalearning.com/en-gb/revision-notes/igcse/computer-science/edexcel-igcse/5-3-11-end-of-topic-test-security.md) ### 6 The Bigger Picture - 6.1 Emerging Trends, Issues & Impact - [6.1.1 E-Waste](https://senecalearning.com/en-gb/revision-notes/igcse/computer-science/edexcel-igcse/6-1-1-e-waste.md) - [6.1.2 Energy Consumption](https://senecalearning.com/en-gb/revision-notes/igcse/computer-science/edexcel-igcse/6-1-2-energy-consumption.md) - [6.1.3 Positive Environmental Impact](https://senecalearning.com/en-gb/revision-notes/igcse/computer-science/edexcel-igcse/6-1-3-positive-environmental-impact.md) - [6.1.4 Ethical Issues - The Digital Divide](https://senecalearning.com/en-gb/revision-notes/igcse/computer-science/edexcel-igcse/6-1-4-ethical-issues-the-digital-divide.md) - [6.1.5 Ethical Issues - Net Neutrality](https://senecalearning.com/en-gb/revision-notes/igcse/computer-science/edexcel-igcse/6-1-5-ethical-issues-net-neutrality.md) - [6.1.6 Ethical Issues - Working Conditions](https://senecalearning.com/en-gb/revision-notes/igcse/computer-science/edexcel-igcse/6-1-6-ethical-issues-working-conditions.md) - [6.1.7 Ethical Issues - Censorship](https://senecalearning.com/en-gb/revision-notes/igcse/computer-science/edexcel-igcse/6-1-7-ethical-issues-censorship.md) - [6.1.8 Online Activity Tracking](https://senecalearning.com/en-gb/revision-notes/igcse/computer-science/edexcel-igcse/6-1-8-online-activity-tracking.md) - [6.1.9 The Internet of Things](https://senecalearning.com/en-gb/revision-notes/igcse/computer-science/edexcel-igcse/6-1-9-the-internet-of-things.md) - [6.1.10 Positive Cultural Impacts](https://senecalearning.com/en-gb/revision-notes/igcse/computer-science/edexcel-igcse/6-1-10-positive-cultural-impacts.md) - [6.1.11 Negative Cultural Impacts](https://senecalearning.com/en-gb/revision-notes/igcse/computer-science/edexcel-igcse/6-1-11-negative-cultural-impacts.md) - [6.1.12 Data Protection Act](https://senecalearning.com/en-gb/revision-notes/igcse/computer-science/edexcel-igcse/6-1-12-data-protection-act.md) - [6.1.13 Computer Misuse Act](https://senecalearning.com/en-gb/revision-notes/igcse/computer-science/edexcel-igcse/6-1-13-computer-misuse-act.md) - [6.1.14 Copyright Designs and Parents Act](https://senecalearning.com/en-gb/revision-notes/igcse/computer-science/edexcel-igcse/6-1-14-copyright-designs-and-parents-act.md) - [6.1.15 Creative Commons Licensing](https://senecalearning.com/en-gb/revision-notes/igcse/computer-science/edexcel-igcse/6-1-15-creative-commons-licensing.md) - [6.1.16 Freedom of Information Act](https://senecalearning.com/en-gb/revision-notes/igcse/computer-science/edexcel-igcse/6-1-16-freedom-of-information-act.md) - [6.1.17 Open Source Software](https://senecalearning.com/en-gb/revision-notes/igcse/computer-science/edexcel-igcse/6-1-17-open-source-software.md) - [6.1.18 Proprietary Software](https://senecalearning.com/en-gb/revision-notes/igcse/computer-science/edexcel-igcse/6-1-18-proprietary-software.md) - [6.1.19 Licensing Issues](https://senecalearning.com/en-gb/revision-notes/igcse/computer-science/edexcel-igcse/6-1-19-licensing-issues.md) - [6.1.20 End of Topic Test - Software & Issues](https://senecalearning.com/en-gb/revision-notes/igcse/computer-science/edexcel-igcse/6-1-20-end-of-topic-test-software-and-issues.md)