One visual cue would be the logo:
The official webpage will tell you more about Emacs.
If this community were a movie, it would be Braveheart.
They may take our lives, but they'll never take... OUR FREEDOM!
(This is because Emacs is closely associated with the GNU project, an operating system composed entirely of Free Software. Emacs users are likely to value the freedom to modify their programs as they wish. This value is intrinsic to the design of Emacs: It is a programming environment for itself, complete with documentation and links to the source code for nearly all its internals.)
This symbol should be avoided:
(The above "Logo of the Beast" is sported by a competitor editor program called "Vim." There is an old rivalry between Emacs and Vi [and Vim, Vi's successor.])