The GCSE Computer Science Workbook is a five-mission revision activity book covering the board-neutral core shared by AQA, Edexcel, OCR and WJEC Eduqas. Students revise systems architecture (the CPU, the fetch-decode-execute cycle, the ALU and control unit, registers, cache, RAM and ROM, and clock speed), data representation (bits and bytes, binary, denary and hexadecimal conversions, ASCII, and lossy versus lossless compression), networks and security (LAN and WAN, packets, protocols such as TCP/IP and HTTP, IP and MAC addresses, malware, phishing, firewalls and encryption), and algorithms, programming and Boolean logic (linear and binary search, bubble and merge sort, data types, sequence, selection and iteration, and AND, OR and NOT truth tables), plus ethical, legal and environmental issues. Missions 1–4 are auto-marked on screen, or the whole book prints with a full answer key. Includes teacher, parent and student notes and is fully SEND-friendly with high-contrast and large-text modes.