Domain name: Computers on the net has unique IP addresses. These addresses contain numbers which are very difficult to remember for us. That’s why, to make it easy to remember they are replaced by alias which are called domain name. These domain names are also unique for each computer. Example : funny.comedian-action.com
Here, .com is the top level domain, comedian-action is the sub domain and funny is an extra bit glued on later.
The top level domains are of fixed purposes. They are as follows,
.com – For commercial organizations
.edu – For educational sites
.org – For non-profitable organizations
.net – For internet service provider
.gov – For government agencies
.mil – For military purpose