Domain name is an identification label that is used to define a particular entity in the World Wide Web with reference to the Domain Name System (DNS). Domains can identify administrative organizations, educational institutions, commercial firms and many more. Domain names are used in various network specific and addressing purposes. Domain names may have different levels, with every network sites having a top-level domain at the end.

The top-level domains or the first-level domains are the names comprising of two or three characters and often describe the type of entity or the location of the entity. The second level domain is placed to the left of a top-level domain, and is generally created by the user of the complete domain. Most organizations prefer their name as the second level domain. A web address may have higher levels of domain to be more specific. The domains are preceded by the hostname of the World Wide Web - “www” and thus make the complete web address.