"For each day is a Kaleidoscope of changing colors, so there's a rainbow in every memory."--dmb--
Historically, a gamer was usually someone who played role-playing games or war games but more recently the term includes computer and video game players as well. While the term technically includes those who don't necessarily consider themselves to be gamers (i.e., casual gamers) it is commonly used to identify people who spend as much of their leisure time as possible playing or reading about games.