In the Domain Name System (DNS) hierarchy, a second-level domain (SLD or 2LD) is a domain that is directly below a top-level domain (TLD). For example...

A top-level domain (TLD) is one of the domains at the highest level in the hierarchical Domain Name System of the Internet after the root domain. The top-level...

Single-letter second-level domains are domains in which the second-level domain of the domain name consists of only one letter, such as x.com. In 1993...

sequence .ac (short for academia) is in use in many countries as a second-level domain for academic institutions such as universities, colleges, and research...

sequence .edu (short for educational) is in use in many countries as a second-level domain for academic institutions such as universities, colleges, and research...

is used as a second-level domain in the Domain Name System used to route internet traffic. Domain registrants register second-level domains of the form...

A country code top-level domain (ccTLD) is an Internet top-level domain generally used or reserved for a country, sovereign state, or dependent territory...

Below these top-level domains in the DNS hierarchy are the second-level and third-level domain names that are typically open for reservation by end-users...

The domain com is a top-level domain (TLD) in the Domain Name System (DNS) of the Internet. Created in the first group of Internet domains at the beginning...

list of Internet top-level domains (TLD) contains top-level domains, which are those domains in the DNS root zone of the Domain Name System of the Internet...