Internal and external hardware
External hardware
Computer
External hardware parts are physical parts that are outside the computer.
Examples :- keyboard, mouse , monitor, pen drive , microphone , scanner , printer, modems , speaker etc.
External hardware devices are also called peripherals.
Modem :-
modem word is made by combination of two words modulator and demodulator.
It is an internet access devices.
Wireless modem is called router.
Internal hardware
Internal hardware parts are inside a box . This box is commercially called CPU.
The main internal parts of a computer are :-
1. CPU
2. Motherboard
3. Hard disk
4. Ram / Rom
5 Ports
Motherboard
It is the actual computer electronic which contains the CPU, ROM , Memory slots of DRAM, Connecting ports visible from outside of the box.
CPU
It is called processing Unit or the microprocessor.
It is considered as brain of computer.
Currently the CPU used in computers and laptops are my series processor of Intel company.
Hard disk
It consists of one or more aluminium discs coated with magnetic material.
It is called hard disk because early disc where flexible made of plastic.
It is external to motherboard.
Currently internal hard disks are available in size of 1 TB.
Hard disc is assembled inside a sealed box containing motors to rotate the disk and read or write head, electronic circuit to process data . This sealed box is called hard disk drive ( HDD ).
Data is arranged in hard disk (also called platter ) in tracks and sectors.
DRAM
DRAM stands for dynamic Random Access Memory . It is a type of ROM.
The other type of RAM is SRAM called Static Random ACCESS Memory.
Standard sizes of DRAM available today are 4 GB , 8 GB.