Understanding Computer Hardware, Software, and Algorithms
What is a Computer?
A computer is a machine capable of performing a sequence of operations based on a program, processing data input.
Main Hardware Components
The main hardware components include the Central Processing Unit (CPU), memory, and input/output devices.
Central Processing Unit (CPU)
The CPU is the ‘brain’ of the computer. It executes data and commands, performs arithmetic and logical operations, and controls other devices.
Memory
Memory stores data and programs temporarily or permanently.
Memory Units of Measurement
- Bit: Binary digit (0 or 1).
- Byte: Character (8 bits).
- Kilobyte (KB): 1024 bytes.
- Megabyte (MB): 1024 KB.
- Gigabyte (GB): 1024 MB.
- Terabyte (TB): 1024 GB.
Memory Rating
Main memory provides fast access. All necessary data and programs must be loaded into main memory for the computer to function.
Types of Main Memory
- ROM (Read-Only Memory): Contains programs for testing and initializing the machine.
- RAM (Random Access Memory): Allows reading and writing information. It is blank when the computer is turned on and loads programs and data.
Boot Disk Files
IO.SYS, MSDOS.SYS, COMMAND.COM, AUTOEXEC.BAT, CONFIG.SYS, DRVSPACE.BIN
Software
Software is the intangible part of a computer, classified into:
- System Software (Operating System)
- Application Software
- Utility Programs
Operating System
The operating system allows interaction between the user and the hardware, making the hardware usable and managing performance. Examples include MS-DOS, OS-2, Windows 95/98/NT, and UNIX.
Application Software
Application software fulfills specific user needs, excluding operating system tasks.
Windows
Windows is a graphical environment designed for many applications, providing a simple and enjoyable user experience. The screen is referred to as a desktop, and functions occur in areas called windows.
Windows Explorer allows browsing files in a hierarchical structure within a single window.
Algorithms
An algorithm is an organized series of steps describing the process to solve a specific problem.
Types of Algorithms
- Qualitative Algorithms: Describe steps using words.
- Quantitative Algorithms: Use numerical calculations to define steps.
Algorithmic Languages
Algorithmic languages use symbols and rules to describe a process explicitly.
Types of Algorithmic Languages
- Graphics: Represent operations using flow charts.
- Non-Graphics: Represent operations descriptively using pseudo code.
Methodology for Solving Problems by Computer
Problem Definition, Problem Analysis, Algorithm Design, Coding, Testing and Debugging, Documentation.
Operators
Operators relate values of variables and constants, allowing manipulation of values.
Arithmetic Operators
Arithmetic operators perform mathematical operations:
- + Addition
- – Subtraction
- * Multiplication
- / Division
- Mod Modulo (remainder of integer division)
- Div Integer division
Relational Operators
Relational operators establish relationships between two values, producing a true or false result:
- > Greater than
- < Less than
- >= Greater than or equal to
- <= Less than or equal to
- <> Not equal to
- = Equals