Computer Hardware

The Physical Components of Computing Systems

What is Computer Hardware?
Definition
Hardware is the physical, touchable components of a computer system. It's everything you can see and touch — like the keyboard, monitor, mouse, CPU cabinet, etc.
Hardware → The Body
Software → The Brain
Example:

A keyboard (hardware) lets you type letters. The typing software (MS Word) shows the letters on screen.

  • Without hardware, software cannot run
  • Without software, hardware is useless
Types of Hardware
Input Devices
Used to give data/instructions to the computer
Examples: Keyboard, Mouse, Scanner, Microphone
When you press "A", binary code (01000001) goes to CPU
Output Devices
Show the processed results from the computer
Examples: Monitor/Screen, Printer, Speakers, Projector
Press Ctrl+P to print your document
Processing Devices (CPU)
The brain of the computer, processes data and controls all activities
CPU Components:
• ALU (Arithmetic Logic Unit)
• CU (Control Unit)
• Registers & Cache
ALU solves: 5 + 3 = 8
Storage Devices
Used to store data permanently or temporarily
Primary (Volatile): RAM
Secondary (Permanent): HDD, SSD
External: Pen drive, CD, DVD
Chrome pages load into RAM
Communication Devices
Used to connect and share data between computers
Examples: Network Interface Card (NIC), Wi-Fi adapter, Modem
Wi-Fi connects you to YouTube
Hardware Examples in Real Life
ATM Machine
Keypad, Card Reader
Input
Screen, Receipt Printer
Output
CPU inside ATM
Processing
ATM's hard disk
Storage
Smartphone
Touchscreen, Camera, Microphone
Input
Screen, Speaker
Output
Mobile Processor (CPU)
Processing
Internal memory, SD card
Storage
Summary
Computer hardware = Input + Output + Processing + Storage + Communication devices
Keyboard (input) sends signal
CPU (processor) processes it
RAM (memory) stores temporarily
Monitor (output) displays it
Hard disk saves permanently