The business of Internet domain names
Buying, selling, developing and monetizing Internet domain names
Navigation
News
Domaining is the business of buying, selling, developing and monetizing Internet domain names.
Domaining Guide
Second-level domain
In the Domain Name System (DNS) hierarchy, a second-level domain (SLD) is a domain that is directly below a top-level domain (TLD). For example, in wikipedia.org, wikipedia is the second-level domain of the .org TLD.
Second-level domains commonly refer to the organization that registered the domain name with a domain name registrar. Some domain name registries introduce a second-level hierarchy to a TLD that indicates the type of organization intended to register an SLD under it. For example, in the .uk namespace a college or other academic institution would register under the .ac.uk ccSLD, while companies would register under .co.uk.
See also
- Domain Name System
- Top-level domain
- Subdomain
- Country code top-level domain
- Single-letter second-level domains