CBSE 10th Class Unit 1 - Basic computer organisation

 

UNIT – 1

CHAPTER - 1

Introduction to Computer System

A computer system is a collection of hardware and software components that work together to process data and produce information.

Hardware

Hardware refers to the physical components of a computer system, such as the CPU, memory, storage devices, input/output devices, and peripherals.

 

                                                computer motherboard with labeled components

Software

Software consists of the programs and instructions that control the hardware and enable it to perform specific tasks. It can be categorized into two main types:

• System software: Manages the computer's hardware and resources, such as the operating system.
• Application software: Performs specific tasks for users, such as word processing, web browsing, and gaming.

Input Devices

Input devices allow users to enter data and instructions into the computer. Common input devices include:

• Keyboard
• Mouse
• Scanner
• Microphone
• Webcam

 

                                        keyboard, mouse, scanner, microphone, and webcam

Output Devices

Output devices display or produce the results of computer processing. Common output devices include:

• Monitor
• Printer
• Speakers
• Projector

 

                                                monitor, printer, speakers, and projector

CPU (Central ProcessingUnit)

The CPU is the brain of the computer, responsible for executing instructions and performing calculations. It consists of two main components: ¹  

• Control Unit: Coordinates the activities of other components.
• Arithmetic Logic Unit (ALU): Performs arithmetic and logical operations.

                                        CPU diagram with control unit and ALU

Memory

Memory stores data and instructions temporarily or permanently. There are three main types of memory:

• Primary Memory (RAM): Volatile memory used to store data and programs that are currently being used by the CPU.
• Cache Memory: A small, fast memory that stores frequently accessed data for quicker retrieval.
• Secondary Memory (Storage): Non-volatile memory used to store data and programs permanently, such as hard drives, SSDs, and USB drives.

                                    RAM chips, a cache memory diagram, and a hard drive

Units of Memory

• Bit: The smallest unit of data, representing a binary digit (0 or 1).
• Byte: 8 bits, typically used to represent a single character.
• Kilobyte (KB): 1024 bytes.
• Megabyte (MB): 1024 KB.
• Gigabyte (GB): 1024 MB.
• Terabyte (TB): 1024 GB.
• Petabyte (PB): 1024 TB.