Top-level domains

Every domain name ends in a top-level domain (TLD) name, which is always either one of a small list of generic names (three or more characters), or a two characters territory code based on ISO-3166 (there are few exceptions and new codes are integrated case by case). Top-level domains are sometimes also called first-level domains.
The generic top-level domain (gTLD) extensions are:

Unsponsored .biz .com .edu .gov .info .int .mil .name .net .org

Sponsored .aero .cat .coop .jobs .mobi .museum .pro .travel

Infrastructure .arpa .root

Startup phase .asia .tel

Proposed .cym .geo .kid .kids .mail .post .sco .web .xxx

Deleted/retired .nato

Reserved .example .invalid .localhost .test

Pseudo-domains .bitnet .csnet .local .onion .uucp

Unofficial see Alternative DNS roots