Sskills Computar - Ro-ràdh

Study Notes

### Compscoil Skills - Introduction

A computer accepts input, stores it temporarily in memory, processes it, and then transfers the processed data to an output device.
Data is raw, unorganized facts.
Information is processed data, organized to be meaningful.
Hardware refers to the physical parts of a computer.
Software are instructions that tell the computer hardware what to do. These are programs.

### Computer Hardware

Internal hardware is located inside the computer's main box.
External hardware connects to the computer, often via wired or wireless connections.
Input devices: Keyboard, mouse, scanner, camera, touchscreen, etc.
Output devices: Monitor, printer, speakers, projector, etc.
Processing devices: CPU (Central Processing Unit) performs calculations and controls the computer's operations.
Storage devices: Hard drives, CDs/DVDs, USB flash drives, etc., used to store data.
Communication devices: MoDems, network adapters, etc.,allow communication with others online.

Software tells the computer what and how to perform tasks.
System software: Main software that starts up and controls the computer's operations.(Examples include operating systems like Windows, Linux.)
Utility programs: Analyze, configure, optimize, and maintain the computer.
Application software is used for specific tasks (Examples include word processors, web browsers, multimedia programs.)
The System Unit is the main housing for the computer's processing hardware, including memory, power supply, cooling fans, and storage devices.

The motherboard is the main circuit board.
It contains computer chips (silicon pieces), circuits (connections), and other electronic components.
All computer components must connect to the motherboard.

Input devices: Accept data from the user and prepare it for processing.
Output devices: Provide results to the user in a human-readable format(e.g., text, graphics).

CPU (Central Processing Unit) is the "brain" of the computer.
Contains electronic circuits that perform processing tasks.
Interprets, processes, and executes instructions.
Includes different cores for parallel processing to improve speed. (e.g., dual-core, quad-core CPUs)

Registers are inside the CPU.
Cache memory is faster than main memory but smaller.
Main memory is relatively fast and stores data needed soon.
Mass storage (hard drive) is large and permanent, but slower.
Cost vs capacity: Cost increases as capacity increases. Faster memory tends to be more expensive.

Bit (Binary digit): 0 or 1.
Byte: 8 bits.
Kilobyte (KB), megabyte (MB), Gigabyte (GB), Terabyte (TB), etc.. represent increasing capacities.

Consists of many transistors and circuits.
A key element of modern CPUs is the transistor.
The number of transistors in a CPU doubles roughly every 18 months.
Typical CPU components: ALU, FPU, CU, Prefetcher, Decoder, Internal Cache, and Registers.

A collection of programs that manage the coordinated activities of a computer system.
Functions: Interfacing with the user, managing resources, booting the system, configuring devices, file management.

Low-level languages (e.g., machine code, assembly): Close to how the hardware operates.
High-level languages (e.g., Fortran, Pascal, C++, Java): Closer to natural language, making them easier for humans to use.
Assembly: Symbolic representation of machine code, more efficient.
High-level language: Consisting of English-like keywords. (e.g., Print, IF-THEN-ELSE).