Post on 26-May-2015
Computer and its functional components
A Computer
What are functional components of a computer?
The computer system is divided into separate units for its operation. These are The arithmetic logical unitThe control unitThe memory unitThe input and output unit
These parts are interconnected by busses, often made of groups of wires.
These are collectively called as Central Processing unit.
Block Diagram of a computer
Arithmetic Logic unit
Control Unit
Memory UnitInput unit Output Unit
Input Devices
Input device is any peripheral used to provide data and control signals to a computer.Some common input devices include:
Keyboard Mouse Joystick Scanner
Keyboard
It is set of typewriter-like keys that enables you to enter data into a computer.
Mouse
A device that controls the movement of the cursor or pointer on a display screen.
Common Input Devices
Output Devices
An output device is any peripheral used to communicate the results of data processing carried out by a computer.
Some Output Devices : Monitor- A display screen Printer Speaker
Printers
A printer is a peripheral which prints text or illustrations on paper.
Types of printers:
• Impact Printers-Work by banging a needle against an ink ribbon to make a mark on paper.
• Non-impact printers-It does not operates by striking a head against an ink ribbon.
Memory Devices
(I) Primary memory: it refers to internal storage areas in a computer. It includes:RAM (random-access memory): We can both write data into RAM and read the data from RAM.
ROM (read-only memory): Permits you only to read data. PROM (programmable read-only memory): A PROM is a memory chip on which you can store a program.EPROM (erasable programmable read-only memory):
Special type of PROM that can be erased by exposing it to ultraviolet light.
Primary memory devices
Secondary memory
Secondary memory is the slowest and cheapest form of memory. It cannot be processed directly by the CPU. It must first be copied into RAM.It includes:Floppy drive is a disk drive that can read and write to a floppy disk. A floppy is small magnetic portable disk. It can store data up to 1.4MB.
Secondary memory devices
Hard Disk: A magnetic disk on which you can store computer data. Hard disks hold more data and are faster than floppy disks. It can store data of more than 100 GB.
Optical Disk: A storage medium from which data is read and to which it is written by lasers. It can store a data up to 6GB.
Project by -Janhavi DevariRoll No: 134