Summary of Introduction to Information and Communication Technology

## Introduction Information and Communication Technology (ICT) is the use of technology to collect, process, store and communicate information. ICT improves communication and productivity across education, business and everyday life. > **Definition:** ICT is the combination of technologies and systems used to manage and share information effectively. ## Core Components of a Computer ### CPU - The **CPU** (Central Processing Unit) is the brain of the computer. It executes instructions and performs calculations. CPU speed is measured in GHz. > **Definition:** The CPU processes program instructions and controls other hardware. ### Memory Types - **RAM (Random Access Memory)**: Stores data currently being used. RAM is volatile; data is lost when power is removed. - **ROM (Read-Only Memory)**: Stores startup instructions and firmware such as the BIOS. ROM is non-volatile. - **Cache Memory**: Very fast memory that stores frequently used data to speed up access. > **Definition:** Volatile memory loses data when power is off; non-volatile memory retains data. Table: Memory comparison | Feature | RAM | ROM | Cache | |---|---:|---:|---:| | Volatility | Volatile | Non-volatile | Volatile | | Typical use | Active programs/data | Startup firmware | Frequently used instructions/data | | Speed | Fast | Slow | Faster than RAM | ### Storage Devices - **HDD (Hard Disk Drive)**: Uses magnetic disks; cheaper but slower and mechanically fragile. - **SSD (Solid State Drive)**: Stores data electronically; faster, more durable, but typically more expensive per GB. - **Cloud Storage**: Stores files on remote servers accessed via the internet; useful for backups and sharing but needs connectivity. > **Definition:** Persistent storage keeps data when the power is off. Fun fact: SSDs have no moving parts, which is why they are less likely to fail due to physical shock than HDDs. ## Input and Output Devices ### Input Devices - Send data into a computer. - Examples: keyboard, mouse, scanner, microphone, touchscreen. > **Definition:** An input device converts user actions or external signals into data the computer can process. ### Output Devices - Present processed information to users. - Examples: monitor, printer, projector, speakers. > **Definition:** An output device converts processed data into human-readable or perceptible form. ## Biometric Authentication - **Biometrics** uses unique physical characteristics to identify people, such as fingerprints and facial recognition. > **Definition:** Biometric systems measure and match physiological or behavioral traits for identity verification. ## Software Basics ### Application Software - Software designed to perform specific tasks for users. Examples: Word, Excel, PowerPoint. ### Software Bugs and Updates - A **software bug** is an error or flaw in a program. Regular updates fix bugs and improve features. > **Definition:** A software update modifies a program to correct faults or add functionality. ## Accessibility - Accessibility features help people with disabilities use computers. Examples include Narrator, Magnifier and Sticky Keys. > **Definition:** Accessibility ensures technology is usable by people with a wide range of abilities. Did you know that built-in accessibility tools like screen readers make digital content usable by visually impaired users? ## Networks and Connectivity ### What is a Network? - A **network** is a group of connected devices that share information and resources. > **Definition:** Networks allow communication and resource sharing between devices. ### Common Network Types - **LAN (Local Area Network)**: Covers a small area such as a school or office. - **PAN (Personal Area Network)**: Connects devices around one person (often via Bluetooth). - **HAN (Home Area Network)**: Network inside a home, typically using Wi-Fi. Table: Network cable types | Cable type | Signal type | Typical use | Speed | |---|---:|---|---:| | UTP | Electrical | Most common LAN c