- The technical information in this article may not be 100% accurate because the details have been summarized.
A Domain is a set of computers on the Internet. The domain name identifies the domain. Many people use the two terms interchangeably. So, for example, someone might say "My domain is example.com," or "My domain name is example.com." Domain names appear in web site URLs and email addresses. "example.com" is the domain in the following examples:
- URL – http://www.example.com
- Email address – firstname.lastname@example.org
The URL shown above has the following components:
- The "http://" part is called a protocol. The protocol informs the network software the rules for transferring the data. For web pages, the protocol is usually "http://" or "https://".
- The "www" part is a hostname. Web servers are often given the hostname "www". Other common hostnames include "pop", "mail", and "smtp" for email-related servers.
- The "example.com" part is the "domain name". The last segment of the domain name, ".com" in this case, is the top-level-domain, or "TLD".
Different hostnames are often used to identify different computers within the same domain. For example, "www1.example.com" might identify one computer within the example.com domain whereas "www2.example.com" might identify a different computer within the domain.
Hostnames are also used to segregate content even when the content is on the same server as a URL with a different hostname. So, for example, "secure.example.com" might be a set of pages on the same server as pages for "www.example.com".
Shared Domain Names
When you publish at many free web hosts, you don't usually get your own domain name. You use theirs instead:
- The hostname has two parts: "genealogy.freepages".
- The domain name is "rootsweb.com".
- The "~johncardinal" part identifies one user of the shared hosting service.
- The "index.htm" part identifies a particular page within the pages published by the user.