Main advantages of computers are:
- It is very fast.
- It gives accurate values.
- It has good memory.
Parts of a Computer:
There are 3 main parts of a computer
- Input Unit
- C.P.U (Central Processing Unit)
- Output Unit.
Input Unit
It is the source through which we give work to the computer. Best examples of standard input devices are keyboard and mouse.
Central Processing Unis (CPU)
It is the brain of the computer. CPU has 3 main parts
- A.L.U (Arithmetic / Logic Unit)
- C.U (Control Unit)
- Memory
Arithmetic/Logic Unit performs arithmetic and logical works.
Control Unit contains all the internal operations of the C.P.U. It decides which work is to be performed by each unit.
Memory is the storage area. Memory is divided into two parts – Primary Memory & Secondary Memory
RAM (Random Access Memory) and ROM (Read Only Memory) comes under primary memory which is also considered as the main memory of the computer. Random Access Memory (RAM) is temporary storage area and the data stored in it is lost as soon as the system is switched off. Read Only Memory (ROM) is permanent memory but only for manufacturer’s purpose.
Hard disk, floppy disk, USB mass storage devices etc., come under secondary memory and it is chiefly used to store data data permanently for future use. Floppy Disks are used to store limited amount of data. Floppies are of 2 major sizes.
- 5 ¼ inches → 1.2 MB Storage Capacity
- 3 ½ inches → 1.44 MB Storage Capacity
Hard Disks are used to store large amounts of data. It houses several times more capacity than a floppy.
Output Unit
It is the source through which we get the data before and after processing. Standard output devices are monitor screen and printer.
