(1) Any combination of alphabetic or numeric characters (A-Z, a-z, or 0-9) and the characters @, #, $, ., !, ?, and _.
(2) In MVS, a group of 1 - 8 characters, including alphanumeric characters and the three characters: #, @, $. The symbol begins with either an alphabetic character or one of the three characters (#,@,$).