TLD stands for Top-Level Domain, and it refers to the highest level of the domain name system (DNS) hierarchy. TLDs are the extensions that come after the final dot in a domain name, such as .com, .org, .net, and .info. The TLD is used to categorize websites into different categories and to provide a recognizable and memorable identifier for a website’s address.

There are two types of TLDs: generic TLDs (gTLDs) and country-code TLDs (ccTLDs). gTLDs, such as .com, .org, .net, and .info, are intended for general use and are not restricted by geographic location. ccTLDs, such as .bd for the Bangladesh and .uk for the United Kingdom, are intended for use by websites associated with a specific country or geographic location.

The availability of TLDs is regulated by the Internet Corporation for Assigned Names and Numbers (ICANN), which is responsible for coordinating the unique identifiers used across the Internet.