Mainly used on bungie.net's The Flood forum, master race is used when, for example, a person is talking about how they love turkey sandwiches. Someone will say how something is better by using the term Master Race.
User 1: I love turkey sandwiches!
User 2: No, Ham Master Race!
People who play PC games on PCs that aren't made by Apple.
Enjoying popular, overrated games like new Call of Duty games (Modern Warfare), World of Warcraft or The Sims excludes one from Master Race.
A gamer who isn't part of the master race is called a peasant.
Enjoy your RRODs, kiddies, no online (and no games), wagglan shovelware, paying for DLC, no upgrades, controllers useless for RTS or FPS and having an useless toy, which only plays (bad) games. At the same time I will enjoy my infinite collection of great games, most of which are better than the sum of garbage you can play on your toys. It feels good being Master Race.