The first LARPs were run in the late 1970s, inspired by tabletop role-playing games and genre fiction. The activity spread internationally during the 1980s and has diversified into a wide variety of styles. Play may be very game-like or may be more concerned with dramatic or artistic expression. Events can also be designed to achieve educational or political goals. The fictional genres used vary greatly, from realistic modern or historical settings to fantastic or futuristic eras. Production values are sometimes minimal, but can involve elaborate venues and costumes. LARPs range in size from small private events lasting a few hours to large public events with thousands of players lasting for days.
LARP has also been referred to as live role-playing (LRP), interactive literature, and free form role-playing. Some of these terms are still in common use; however, LARP has become the most commonly accepted term. It is sometimes written in lowercase, as larp. The live action in LARP is analogous to the term live action used in film and video to differentiate works with human actors from animation. Playing a LARP is often called larping, and one who does it is a larper.
The participants in a LARP physically portray characters in a fictional setting, improvising their characters' speech and movements somewhat like actors in improvisational theatre. This is distinct from tabletop role-playing games, where character actions are described verbally. LARPs may be played in a public or private area and may last for hours or days. There is usually no audience. Players may dress as their character and carry appropriate equipment, and the environment is sometimes decorated to resemble the setting. LARPs can be one-off events or a series of events in the same setting, and events can vary in size from a handful of players to several thousand.
Events are put on for the benefit of the players, who take on roles called player characters (PCs) that the players may create themselves or be given by the gamemasters. Players sometimes play the same character repeatedly at separate events, progressively developing the character and its relations with other characters and the setting.
Arrangers called gamemasters (GMs) determine the rules and setting of a LARP, and may also influence an event and act as referees while it is taking place. The GMs may also do the logistical work, or there may be other arrangers who handle details such as advertising the event, booking a venue, and financial management. Unlike the GM in a tabletop role-playing game, a LARP GM seldom has an overview of everything that is happening during play because numerous participants may be interacting at once. For this reason, a LARP GM's role is often less concerned with tightly maintaining a narrative or directly entertaining the players, and more with arranging the structure of the LARP before play begins and facilitating the players and crew to maintain the fictional environment during play.