A domain name is a unique name that identifies a website or web page on the internet. It is used to access websites, online services, or other resources on the internet. It also serves as a way to differentiate one website from another.

Domain names are made up of two parts: the top-level domain (TLD) and the second-level domain (SLD). The top-level domain is the ending of the domain name and is usually two to three letters long. Examples of top-level domains are .com, .net, .org, .edu, .gov, and .mil. The second-level domain is the first part of the domain name and is typically a word or phrase that represents the website.

When registering a domain name, it is important to choose one that is easy to remember and relevant to the content of the website. It should also be unique enough that it is not already taken by another website. Domain names are often registered through a web hosting company or domain name registrar.

Once registered, the domain name can then be used to access the website or resource it is associated with. Domain names are a necessary part of the internet, as they provide an easy way to access websites and other resources. Without them, it would be difficult to find websites, as users would have to remember a long string of numbers to access them.