TOPIC 3: COMPUTER HARDWARE

Objectives  
By the end of the topic, learners should be able to;

  • define a hardware device.
  • name all the hardware devices used by the computer system.
  • give functions of each of the hardware devices
Introduction to Hardware
Computer equipment is called hardware because it’s built from wires, screws, and other parts you can buy in hardware & electronics stores.
I/O (Input/Output)
The info that the computer gives out is called the computer’s output: it includes the computer’s answers and reports. The info that the computer takes in is called the input: it includes your questions and commands.
The computer hardware that that handle input and output are called input/output devices (I/O devices). The most popular I/O devices to buy are a keyboard, monitor, mouse, printer, microphone, modem (which connects to the phone system), and speakers.
3 types of hardware
For a computer to work fully, you must buy 3 types of hardware:
The processor does the thinking itself; it processes info.
The memory remembers the computer’s thoughts; it includes RAM, ROM, disks.
The I/O devices communicate those thoughts.
Each type is important and useful. A computer without memory is as useless as a person who says “I had a great idea but can’t remember it.” A computer without an input/output system is as useless as a person who says, “I had a great idea and remember it but won’t tell you.”
When you’re buying a computer, check all 3 types and make sure they’re good. This book explains how to judge them.

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