A number of gangs appear in GTA V, and have minor interaction with the three protagonists throughout the course of the storyline. Members from specific gangs can be found hanging around in groups in certain neighbourhoods around San Andreas (particularly evident in the South Los Santos area) and will generally react to your actions. For example, if you pull out a gun around some gang members, expect them to do the same right back at you. Gang members may also become hostile if you hang around their turf for too long, regardless of the gang or the character you are playing as. The time of day will also determine the behaviour you can expect from gang members. For example, during the day; gangs may be more timid and less visible then they are during the night. Rival gangs and sets may also occasionally be seen in shootouts as well.

Families

The Families are an African-American street gang that can predominately be seen around the Chamberland Hills and Strawberry neighbourhoods. They have a bitter rivalry with the Ballas; however there is also infighting between the various sets of the Families, being the Carson Avenue Families, Forum Drive Families and the Chamberlain Gangster Families. One of the main protagonists, Franklin, has had involvement in the gang.

They wear green as their primary colour and are predominately seen around Forum Drive in South Los Santos, as well as the area surrounding it.


Ballas

The Ballas are an African-American street gang which control the entire neighbourhood of Davis, in South Los Santos; with Grove Street in particular being a hotbed for activity. They have a bitter rivalry with all sets of the Families, and there are a few missions that involve shootouts with the gang - which predominately involve Franklin as the lead character.

Ballas gang members wear purple as their primary colour can be seen hanging around in pretty much any area of Davis.


Los Santos Vagos

The Vagos are a Hispanic street gang who control most of the neighbourhood of Rancho. They also appear mission "Repossession" in which Franklin and Lamar must shoot their way out of a Vagos infested neighbourhood.

Jamestown Street, and the housing projects to the south of Rancho are particular hotspots for Vagos activity.


Various Los Aztecas

The Aztecas are involved in drug trafficking as well as arms trafficking. They have a rivalry with Trevor Philips, one of the three main protagonists, and seek vengeance after he kills one of their members, Ortega. They will also appear as rivals in arms trafficking missions.

Azteca gang members can be seen around Northern Rancho behind the Central Los Santos Hospital.


The Lost Brotherhood

The Lost MC is an outlaw motorcycle gang originating in Liberty City, however has since either branched out to or relocated completely to Los Santos. They have a rivalry with Trevor Philips and this rivalry leads to the gang pretty much loosing all its influence in Blaine County. 

The Lost MC also have a clubhouse in East Vinewood, on Mirror Park Blvd, and can be seen hanging around this area. They can also be occasionally seen riding around in groups of three around Blaine County as well.