What is Computer Network ?

A Computer Network is group of computer/Devices are interconnected together for the purpose of exchange data . Each Computers on a network are called nodes. The connection between computers can be done through cabling (most common Ethernet cable) or wireless through radio waves. All connected computers can share resources, like access to the Internet, printers, file servers, and others.
Example:
Just to understand basic network, we can take an example of postal system .Lets take an example, Person (A) in Sandy springs ST,Atlanta wants to send letter to Person (B) in Randolph St,Chicago. In this particular scenario if we think about postal system , first letter will be dispatch to local Sandy Springs office then letter will be send to Central office . When Central office see the letter is for Chicago then letter will be dispatch to Chicago local post office and from Chicago local post office letter will be dispatch to Randolph St,Chicago. In this particular example, letter is working as data and two end point are working as computers.

A Computer network can be break down in two part –
• Local Area Network (LAN)
• Wide Area Network (WAN)