25-08-2017, 09:32 PM
Introduction to computers
Introduction to Computer.docx (Size: 119.88 KB / Downloads: 23)
Definition of a Computer
A computer can be defined as an electronic device that receives input from the user through a mouse or keyboard, processes it in some fashion and displays the result on a screen. It can also be assumed as any device that has a microprocessor in it.
Basic Units of a Computer
Modular units usually consist of the following separate components:
• The Computer
• The Monitor
• The Keyboard
• The Mouse
• Peripherals
Central Processing Unit (CPU)
Central processing unit (CPU): The heart of the computer, this is the component that actually executes instructions organized in programs ("software") which tell the computer what to do.
Storage Devices
Memory(fast, expensive, short-term memory): Enables a computer to store, at least temporarily, data, programs, and intermediate results.
Mass storage device (slower, cheaper, long-term memory): Allows a computer to permanently retain large amounts of data and programs between jobs. Common mass storage devices include disk drives and tape drives.
Input Devices
1. Keyboard
2. Mouse
3. Joystick
4. Light pen
5. Digial Camera
6. Microphone
7. Touch screen
8. Scanner
9. OCR (Optical Character Recognition)
Output Devices
1. Monitors or Visual Display Units (VDUs)
2. Printers
Other devices
1. Speakers
2. LCD projectors
TYPES OF COMPUTERS
Computers can be classified based on their principles of operation or on their configuration. By configuration, we mean the size, speed of doing computation and storage capacity of a computer.