This isn’t a frequently asked question, but it should be! A variety of informational files about Emacs and relevant aspects of the GNU project are available for you to read.
The following files (and others) are available in the etc directory of the Emacs distribution (see File-name conventions, if you’re not sure where that is). Many of these files are available via the Emacs ‘Help’ menu, or by typing C-h ? (M-x help-for-help).
GNU General Public License
Emacs Availability Information
The GNU Manifesto
Status of Emacs on Various Machines and Systems
Emacs news, a history of recent user-visible changes
More GNU information, including back issues of the GNU’s Bulletin, are at