**NEW J277 SPECIFICATION: ** Here you will find easy to follow revision sheets which will help your students to recap the topic: 2.5 – Programming languages and Integrated Development Environments 2.5.1 Languages Characteristics and purpose of different levels of programming language: o High-level languages o Low-level languages The purpose of translators The characteristics of a compiler and an interpreter 2.5.2 The Integrated Development Environment (IDE) Common tools and facilities available in an Integrated Development Environment (IDE): o Editors o Error diagnostics o Run-time environment o Translators

NEW J277 SPECIFICATION: Here you will find easy to follow revision sheets which will help your students to recap the topic: 2.4 – Boolean logic Simple logic diagrams using the operators AND, OR and NOT Truth tables Combining Boolean operators using AND, OR and NOT Applying logical operators in truth tables to solve problems The revision sheets include exam questions at the end of each topic to help the students recap their revision and apply it to a question. Enjoy!

NEW J277 SPECIFICATION: Here you will find easy to follow revision sheets which will help your students to recap the topic: 2.3 Producing Robust Programs ¨ Defensive design considerations: o Anticipating misuse o Authentication ¨ Input validation ¨ Maintainability: o Use of sub programs o Naming conventions o Indentation o Commenting ¨ The purpose of testing ¨ Types of testing: o Iterative o Final/terminal ¨ Identify syntax and logic errors ¨ Selecting and using suitable test data: o Normal o Boundary o Invalid/Erroneous ¨ Refining algorithms The revision sheets include exam questions at the end of each topic to help the students recap their revision and apply it to a question. Enjoy!

NEW J277 SPECIFICATION: Here you will find easy to follow revision sheets which will help your students to recap the topic: 2.2 – Programming fundamentals ¨ The use of variables, constants, operators, inputs, outputs and assignments ¨ The use of the three basic programming constructs used to control the flow of a program: o Sequence o Selection o Iteration (count- and condition-controlled loops) ¨ The common arithmetic operators ¨ The common Boolean operators AND, OR and NOT The use of data types: o Integer o Real o Boolean o Character and string o Casting The use of basic string manipulation ¨ The use of basic file handling operations: o Open o Read o Write o Close ¨ The use of records to store data ¨ The use of SQL to search for data ¨ The use of arrays (or equivalent) when solving problems, including both one-dimensional (1D) and two-dimensional arrays (2D) ¨ How to use sub programs (functions and procedures) to produce structured code ¨ Random number generation The revision sheets include exam questions at the end of each topic to help the students recap their revision and apply it to a question. Enjoy!

NEW J277 SPECIFICATION: Here you will find easy to follow revision sheets which will help your students to recap the topic: 2.1 – Algorithms Principles of computational thinking: o Abstraction o Decomposition o Algorithmic thinking Identify the inputs, processes, and outputs for a problem ¨ Structure diagrams ¨ Create, interpret, correct, complete, and refine algorithms using: o Pseudocode o Flowcharts o Reference language/high-level programming language ¨ Identify common errors ¨ Trace tables Standard searching algorithms: o Binary search o Linear search ¨ Standard sorting algorithms: o Bubble sort o Merge sort o Insertion sort The revision sheets include exam questions at the end of each topic to help the students recap their revision and apply it to a question. Enjoy!

NEW J277 SPEC Here you will find easy to follow revision sheets which will help your students to recap the topic: 1.6 Ethical, Legal, Cultural and Environmental Impacts of Digital Technology ¨ Impacts of digital technology on wider society including: o Ethical issues o Legal issues o Cultural issues o Environmental issues o Privacy issues ¨ Legislation relevant to Computer Science: o The Data Protection Act 2018 o Computer Misuse Act 1990 o Copyright Designs and Patents Act 1988 o Software licences (i.e. open source and proprietary)

NEW J277 SPECIFICATION Here you will find easy to follow revision sheets which will help your students to recap the topic: 1.5 Systems Security The purpose and functionality of operating systems: o User interface o Memory management and multitasking o Peripheral management and drivers o User management o File management 1.5.2 Utility software ¨ The purpose and functionality of utility software ¨ Utility system software: o Encryption software o Defragmentation o Data compression

NEW J277 SPECIFICATION Here you will find easy to follow revision sheets which will help your students to recap the topic: 1.4 Network Security 1.4.1 Threats to computer systems and networks ¨ Forms of attack: o Malware o Social engineering, e.g. phishing, people as the ‘weak point’ o Brute-force attacks o Denial of service attacks o Data interception and theft o The concept of SQL injection 1.4.2 Identifying and preventing vulnerabilities ¨ Common prevention methods: o Penetration testing o Anti-malware software o Firewalls o User access levels o Passwords o Encryption o Physical security

NEW J277 SPECIFICATION Here you will find easy to follow revision sheets which will help your students to recap the topic: 1.3 Computer Networks, Connections and Protocols 1.3.1 Networks and topologies ¨ Types of network: o LAN (Local Area Network) o WAN (Wide Area Network) ¨ Factors that affect the performance of networks ¨ The different roles of computers in a client-server and a peer-topeer network ¨ The hardware needed to connect stand-alone computers into a Local Area Network: o Wireless access points o Routers o Switches o NIC (Network Interface Controller/Card) o Transmission media ¨ The Internet as a worldwide collection of computer networks: o DNS (Domain Name Server) o Hosting o The Cloud o Web servers and clients ¨ Star and Mesh network topologies 1.3.2 Wired and wireless networks, protocols and layers ¨ Modes of connection: o Wired • Ethernet o Wireless • Wi-Fi • Bluetooth ¨ Encryption ¨ IP addressing and MAC addressing ¨ Standards ¨ Common protocols including: o TCP/IP (Transmission Control Protocol/Internet Protocol) o HTTP (Hyper Text Transfer Protocol) o HTTPS (Hyper Text Transfer Protocol Secure) o FTP (File Transfer Protocol) o POP (Post Office Protocol) o IMAP (Internet Message Access Protocol) o SMTP (Simple Mail Transfer Protocol) ¨ The concept of layers

NEW J277 SPECIFICATION Here you will find easy to follow revision sheets which will help your students to recap the topic: 1.2 Storage and Memory which includes: The need for primary storage The difference between RAM and ROM The purpose of ROM in a computer system The purpose of RAM in a computer system Virtual memory ¨ The need for secondary storage ¨ Common types of storage: o Optical o Magnetic o Solid state ¨ Suitable storage devices and storage media for a given application ¨ The advantages and disadvantages of different storage devices and storage media relating to these characteristics: o Capacity o Speed o Portability o Durability o Reliability o Cost ¨ The units of data storage: o Bit o Nibble (4 bits) o Byte (8 bits) o Kilobyte (1,000 bytes or 1 KB) o Megabyte (1,000 KB) o Gigabyte (1,000 MB) o Terabyte (1,000 GB) o Petabyte (1,000 TB) ¨ How data needs to be converted into a binary format to be processed by a computer ¨ Data capacity and calculation of data capacity requirements Numbers ¨ How to convert positive denary whole numbers to binary numbers (up to and including 8 bits) and vice versa ¨ How to add two binary integers together (up to and including 8 bits) and explain overflow errors which may occur ¨ How to convert positive denary whole numbers into 2-digit hexadecimal numbers and vice versa ¨ How to convert binary integers to their hexadecimal equivalents and vice versa ¨ Binary shifts Characters ¨ The use of binary codes to represent characters ¨ The term ‘character set’ ¨ The relationship between the number of bits per character in a character set, and the number of characters which can be represented, e.g.: o ASCII o Unicode Images ¨ How an image is represented as a series of pixels, represented in binary ¨ Metadata ¨ The effect of colour depth and resolution on: o The quality of the image o The size of an image file Sound ¨ How sound can be sampled and stored in digital form ¨ The effect of sample rate, duration and bit depth on: o The playback quality o The size of a sound file ¨ The need for compression ¨ Types of compression: o Lossy o Lossless The revision sheets include over 50 exam questions at the end of each topic to help the students recap their revision and apply it to a question. Enjoy!

NEW J277 SPECIFICATION: Here you will find easy to follow revision sheets which will help your students to recap the topic: 1.1 Systems Architecture which includes: The purpose of the CPU: o The fetch-execute cycle ¨ Common CPU components and their function: o ALU (Arithmetic Logic Unit) o CU (Control Unit) o Cache o Registers ¨ Von Neumann architecture: o MAR (Memory Address Register) o MDR (Memory Data Register) o Program Counter o Accumulator How common characteristics of CPUs affect their performance: o Clock speed o Cache size o Number of cores ¨ The purpose and characteristics of embedded systems ¨ Examples of embedded systems The revision sheets include exam questions at the end of each topic to help the students recap their revision and apply it to a question. Enjoy!

Here you will find easy to follow revision sheets which will help your students to recap the topic: 2.6 Data Representation Units bit, nibble, byte, kilobyte, megabyte, gigabyte, terabyte, petabyte how data needs to be converted into a binary format to be processed by a computer. Numbers how to convert positive denary whole numbers (0–255) into 8 bit binary numbers and vice versa how to add two 8 bit binary integers and explain overflow errors which may occur binary shifts how to convert positive denary whole numbers (0–255) into 2 digit hexadecimal numbers and vice versa how to convert from binary to hexadecimal equivalents and vice versa check digits. Characters the use of binary codes to represent characters the term ‘character-set’ the relationship between the number of bits per character in a character set and the number of characters which can be represented (for example ASCII, extended ASCII and Unicode). Images how an image is represented as a series of pixels represented in binary metadata included in the file the effect of colour depth and resolution on the size of an image file. Sound how sound can be sampled and stored in digital form how sampling intervals and other factors affect the size of a sound file and the quality of its playback: sample size bit rate sampling frequency. Compression need for compression types of compression: lossy lossless. The revision sheets include exam questions at the end of each topic to help the students recap their revision and apply it to a question. Check out my shop to save on buying multiple sheets!! Enjoy!