Get the latest tech news
Public Suffix List
A "public suffix" is one under which Internet users can (or historically could) directly register names. Some examples of public suffixes are .com, .co.uk and pvt.k12.ma.us.
A "public suffix" is one under which Internet users can (or historically could) directly register names. The Public Suffix List is an initiative of Mozilla, but is maintained as a community resource. Avoid privacy-damaging "supercookies" being set for high-level domain name suffixes Highlight the most important part of a domain name in the user interface Accurately sort history entries by site
Or read this on Hacker News