What Is a Top Level Domain?

Top level domain is a thing that comes at the end of a u r o, before the slashes specific to the web site. So like dot com, dot e d, dot o r g, these are the common ones. Each country has its own and then there's ed for university. But it's not like, up until now, it's oli just have anything, right? And so they're allowing companies to register top level domains.