What is a trademark?

A brand identifier

A trademark is generally a word, phrase, symbol, or design, or a combination thereof, that identifies and distinguishes the source of the goods. A service mark is the same as a trademark, except that it identifies and distinguishes the source of a service rather than goods.

Once registered, that same symbol or series of words cannot be used by any other organization, forever, as long as it remains in use and proper paperwork and fees are paid.