Computer Fundamentals and Types

Study Notes

A programmable electronic device that processes data and produces output based on a set of instructions called a program.
Types of computers include analog, digital, and hybrid.

Embedded computers: small, specialized computers built into larger devices.
Mobile devices: portable computers with cellular connectivity.
Personal computers: general-purpose computers for individual use.
Midrange servers: powerful computers designed for multi-user use.
Mainframe computers: large, powerful systems capable of handling massive amounts of data.
Supercomputers: the most powerful computers designed for complex calculations and simulations.

The physical components of a computer.
Central Processing Unit (CPU): Performs arithmetic and logical operations, controls data movement, and executes instructions.
- ALU: Arithmetic Logic Unit, handles math and logic operations.
- Control Unit: Coordinates data flow and instruction execution.
- Registers: High-speed storage units for temporary data.
Memory: Stores data and instructions.
- Primary Memory: Directly accessible by the CPU, including:
  - RAM: Random Access Memory, volatile memory used for active data.
  - ROM: Read-Only Memory, non-volatile memory holding permanent instructions.
- Secondary Memory: External storage not directly accessible to the CPU, providing permanent long-term storage, such as hard disks, DVDs, USB drives, etc.
Input devices: Allow users to provide data to the computer, such as keyboards, mice, webcams, barcode scanners, microphones, touch screens.
Output devices: Display processed information from the computer, such as monitors, printers, speakers, projectors, plotters.

Programs and instructions that tell the computer hardware what to do.
Computer programming: The process of creating sequences of instructions for computers.
Types of software:
- System software: Programs designed to manage and control hardware and run application programs.
- Application software: Programs designed for end users to perform specific tasks.
- Operating Systems: System software that manages and controls computer hardware, runs other programs, and interacts with the user. Examples: DOS, Windows, Unix, Linux, Mac OSX.

Similar to human languages, using a specific syntax and reserved keywords.
Can be classified as:
- High-level Languages: Portable and use more human-readable instructions (ex: Cobol, Basic, C, C++, C#, Java).
- Assembly Language: Uses mnemonics (English-like terms) to create instructions for specific machines.
- Machine Languages: Uses binary code (1s and 0s) to create instructions directly understood by the computer.

Pseudocode: Using natural language to outline the steps of an algorithm (e.g., using English).
Flowchart: Using a diagram to visually represent the flow of a program and its steps.

Assembler: Translates assembly language code into machine code.
Interpreter: Translates high-level language code into machine code line by line.
Compiler: Translates high-level language code into machine code (executable file).

Also known as modular programming.
Focuses on logical structure rather than data organization.
Uses a top-down approach to divide programs into smaller, logical blocks of code called functions.
Each function performs a specific task, making programs easier to understand and modify.