Public Suffix List

A list of domain endings under which people can register names, such as .com and co.uk. Volunteers under Mozilla maintain it, with submissions from registries (glossary)registry The central database and system of a top-level domain, or loosely the organization that runs it. Full definition of registry, and it is not complete. Its private section also lists service domains where users create subdomains (glossary)subdomain A name created under a registered domain, like shop.example.com. Full definition of subdomain. Browsers and other software use it to tell where one owner's domain ends and another begins.