Wherever you come across this initialism, you are being referred to Generic Top-Level Domains. These refer to top-level domains, which is to say the text at the very end of any URL or web address. Here are some of the most common gTLDs out there:
- .com
- .org
- .net
- .gov
- .edu
- .digital
They’re managed by an organisation called the Internet Assigned Numbers Authority (IANA), and new gTDLs are added to the list from time to time. Importantly, there are also ccTDLs, which are Country Code Top-Level Domains. In the UK, for instance, .co.uk is a ccTLD, not a gTLD.