CS Full Summary.docx

Binary

Binary

A base-2 numeral system used by computers to represent data and program instructions with each digit being a bit.

Signed Integers

Negative integers represented in binary using sign and magnitude or two’s complement, where the leftmost bit is the Most Significant Bit (MSB).

Shifts and overflows

Techniques in binary arithmetic including logical and arithmetic shifts, where overflow occurs when the value exceeds the maximum storable value.

Hexadecimal Notation

A base-16 numeral system used to store larger numbers efficiently and convert between hexadecimal and binary easily.

ASCII and Unicode

ASCII is a 7-bit character set encoding text data, while Unicode is a character set encoding all characters using 8-bit, 16-bit, or 32-bit encoding.

Bitmap images

Images represented in binary through pixels, resolution, and color depth, where the file size is determined by multiplying resolution and color depth.

Sound in Binary

Representation of sound in binary through analog-to-digital conversion, involving sample rate and bit depth to store analog data digitally.

Binary Multiples

Understanding and converting between binary and denary multiples like bits, nibbles, bytes, kilobytes, megabytes, gigabytes, and terabytes.

Data Compression

Techniques to reduce data size including lossy and lossless compression methods like JPEG and MP3 algorithms.

Data Encryption

Scrambling data to make it unreadable to unauthorized users using symmetric and asymmetric encryption methods like HTTPS connections.

IPO Model

Input-Process-Output model describing the structure of information processing programs with input, process, and output levels.

Computational Models

Range of computational models including sequential, parallel, and multi-agent models to study and describe algorithms.

Hardware Components

Functions of computer hardware components like CPU, main memory, secondary storage, and input/output devices and how they work together.

Types of Memory

Understanding different memory types like RAM, ROM, cache, and virtual memory and their functions in a computer system.

Virtual Memory

Increases physical memory efficiency but can lead to performance decline due to swap speed and disk thrashing.

Von Neumann Model

Stores programs as data and instructions in the same memory, involving the fetch-decode-execute cycle.

Fetch-Decode-Execute Cycle

Processor follows this cycle to process instructions, involving fetch, decode, and execute stages.

Control Unit

Executes instructions, generates control signals, and ensures component synchronization through clock signals.

Arithmetic Logic Unit (ALU)

Performs calculations and logical operations within the CPU.

Clock

Generates signals to synchronize CPU actions, determining the speed of the fetch-decode-execute cycle.

Register

Short-term memory store close to the CPU, holding various types of data.

Buses

Cables carrying data between different parts of the computer, including address, data, and control buses.

CPU Performance Factors

Include clock speed, number of processor cores, cache size, and cache type, affecting CPU efficiency.

Physical Storage Types

Include magnetic, optical, and solid-state storage, each with unique characteristics and advantages.

Cloud Storage

Involves storing data among multiple servers hosted by a company, offering cybersecurity and accessibility benefits.

Embedded Systems

Designed for specific tasks, these systems are cost-effective, low-power, and often interconnected by the Internet.

Operating System

Manages files, processes, hardware, and the user interface, providing essential functions for computer operation.

Utility Software

Includes tools for managing, repairing, and converting files, as well as compression, defragmentation, and security functions.

Simulation Software

Used to model real-world aspects for testing purposes, requiring powerful processors for accurate results.

System Software vs

System software enables computer operation, while application software performs specific tasks for users.

High-Level Languages

Offer strong abstraction and ease of understanding for programmers, requiring compilers or interpreters for execution.

Language Processors

Include assemblers, compilers, and interpreters, each with advantages and disadvantages in translating programming languages.

Networks

Connect electronic devices for communication, sharing resources, and centralized management, but can pose security risks.

Network Types

Include LANs, WANs, and PANs, each serving different geographical areas and usage models like client-server and peer-to-peer.

Wired and Wireless Connections

Differ in transmission methods, speed, security, and installation requirements, offering unique advantages and disadvantages.

Network Protocols

Define communication rules between devices, including HTTP, HTTPS, TCP/IP, Ethernet, Wi-Fi, FTP, and email protocols.

File Transfer Protocol (FTP)

Used in the application layer for transferring files over TCP/IP stacks, typically unencrypted.

IMAP, POP3, and SMTP

Email application protocols in the application layer for storing, downloading, and sending emails.

Transmission Control Protocol (TCP)

Transport layer protocol that breaks down data into packets, assigns sequence numbers, and ensures data integrity.

Internet Protocol (IP)

Network layer protocol assigning source/destination IP addresses and moving packets between network nodes.

Ethernet

Link layer protocol for wired LANs, standardizing physical and data link layers.

Wi-Fi

Link layer protocol for WLANs, standardizing wireless data transmission.

4-Layer TCP/IP Model

Describes the layered protocol stacks including application, transport, network, and data link layers.

Bus Topology

Network topology where devices are connected by a single cable, managing collisions with CSMA/CD.

Ring Topology

Network topology with devices in a closed loop, allowing easy addition of devices but prone to failures.

Star Topology

Network topology where devices connect to a central point, ensuring no data collisions.

Mesh Topology

Network topology where devices are connected to many others, offering high performance but difficult to manage.

Mobile Networks (3G, 4G, 5G)

Generations of mobile technology offering wireless access to the Internet with varying speeds and encryption levels.

Network Security

Importance of securing networks through validation, authentication, access control, physical security, and firewalls.

Cyber Attacks

Different forms of attacks like phishing, shoulder surfing, unpatched software, USB devices, and eavesdropping.

Vulnerability Detection

Methods like penetration testing, ethical hacking, commercial tools, and policy reviews to identify weaknesses.

Cyberprotection

Techniques to protect software systems from attacks, including audit trails, secure coding, and effective network security.

Internet

Global network structured with IP addressing and domain name systems for identifying devices and translating domain names.

World Wide Web (WWW)

Collection of web pages accessed through web browsers, ISPs, and protocols like HTTP/S and HTML.

IPv4 and IPv6

IP addressing standards with IPv4 using 4 bytes and IPv6 using 16 bytes for addresses.

Internet Access Components

Modems, routers, switches, and wireless access points combine to provide internet connectivity.

Encryption

Technique that prevents unauthorized access to data by converting it into a code

Cookie cleaners

Software designed to detect and remove small data files that track browsing history

Anti-spyware program

Software that protects against spyware, which gathers information without consent

Identity management service

Third-party entity providing identifiers for secure transactions without revealing personal information

Digital Inclusion

Ensuring affordable access to technology for all individuals

Digital divide

Disparity in access to technology due to bans, affordability, or lack of resources

Professionalism

Ethical behavior adhering to the British Computer Society's code of conduct

Intellectual property

Unique creative products with commercial value protected by copyrights

Licensing

Terms specifying the use of software copies to prevent unauthorized distribution

Open software

Freely available software that can be modified and built upon by users

Proprietary software

Protected software that cannot be modified or redistributed without permission

Computer Misuse Act

Legislation preventing unauthorized access to computer systems

AI

Machines capable of performing tasks at the level of intellectual beings like humans

DNA Computing

Storing data using DNA's properties for faster and more efficient processing

Nanotechnology

Technology reducing the size of transistors for various applications like self-cleaning glass and medicine

Quantum computing

Utilizing qubits to perform calculations faster and more efficiently than traditional computers