A high-level domain (HLD), also known as a top-level domain (TLD), refers to the last segment of a domain name in the Domain Name System (DNS) hierarchy. It represents the highest level in the hierarchical structure of internet domain names and is located at the end of a web address following the final dot.
There are various categories of top-level domains, each serving different purposes and often categorising websites based on their type, purpose, or geographic location. Some common categories of TLDs include:
- Generic TLDs (gTLDs): These are generic and not tied to any specific country. Examples include .com, .org, .net, .info, .biz, and newer ones like .app, .blog, .guru, etc.
- Country Code TLDs (ccTLDs): These represent specific countries or territories and are based on their two-letter country codes, such as .us (United States), .uk (United Kingdom), .de (Germany), .fr (France), etc.
- Sponsored TLDs (sTLDs): These are specialised TLDs created for specific communities or sponsored by private or governmental organisations. Examples include .edu (for educational institutions), .gov (for government entities), .mil (for the military), and others.
- Infrastructure TLDs: These include TLDs like .arpa, used for technical infrastructure purposes.
While each country has autonomy to manage its own HLDs, the Internet Corporation for Assigned Names and Numbers (ICANN) oversees the allocation and management of high-level domains, ensuring their proper functioning, domain registration policies, and the introduction of new TLDs.