In order to become "top dog" of the game the player must race and defeat opponents through a variety of different stages all set in Los Angeles's infamous South Central region.
The game's title comes from two phrases common in the subculture. 187 is the California Penal Code section that defines murder. It has come into general use among gangs in the United States as a synonym for murder, and this usage has passed into popular culture via gangsta rap. "Ride or die" is a combination of the phrases "ride it out" and "die trying", meaning one is willing to do anything even if it involves personal risk.
If playing with another player, one can be the driver and the other can be the shooter. This can be done in the story and online mode. There are a variety of modes available to the player.