Second-level Domain

An SLD (Second Level Domain) is a domain that is hierarchically directly below a TLD.

It is usully used as a way to differenciate various functions of a server or to delimit areas under the same domain. For example, www is a commonly used SLD to indicate the domain points to a web server.

As another example, in, the developer SLD is used to specify that the subdomain contains the developer section of the mozilla website.

Learn more

  • SLD on Wikipedia

Document Tags and Contributors

 Contributors to this page: klez
 Last updated by: klez,