Prior to GURPS, role-playing games of the 1970s and 1980s were developed especially for certain gaming environments, and they were largely incompatible with one another. For example, TSR (the publisher of the Dungeons & Dragons game) published its D&D game specifically for a "fantasy" environment. Another game from the same company, Star Frontiers, was developed for science fiction-based role-playing. TSR produced other games for other environments, such as Gamma World, Top Secret, Gangbusters, and more. Each of these games was set with its own self-contained rules system, and the rules for playing each game differed wildly from one game to the next. GURPS is an attempt to create an all-encompassing, "universal" role-playing system that allows players to role-play in any environment they please without having to create a new set of rules for each game.
GURPS is not the first role-playing system to present a "universal" set of rules for different gaming environments. The Chaosium role-playing system, best known for the highly successful Call of Cthulhu and Runequest role-playing games, were also developed to be a "generic" set of role-playing rules. However, GURPS is part of the first wave of role-playing games that eschews random generation of characters in favor of a point-based system. Role-playing games of the 1970s and 1980s, such as Dungeons & Dragons, use random numbers generated by dice rolls to assign statistics to player characters. GURPS, in contrast, assigns each player a specified number of points for each category of their characters. Together with the Hero_System, GURPS was one of the first role-playing games in which characters are created by spending points to get characteristics, skills, advantages, getting more point by accepting low characteristics, disadvantages etc. Most other role-playing systems generate character characteristics using dice.
Gamers generally see GURPS as an attempt to appeal to beginners to role-playing, by abandoning a number of archaic (but profitable) idiosynchracies unique to role-playing games. With its "generic" design and its use of only standard six-sided dice (rather than the polyhedral dice used in other systems), it places an emphasis on role-playing rather than on deciphering complicated rulebooks.
GURPS' emphasis on its "generic" aspect has proven to be a successful marketing tactic: it is one of the more popular role-playing games on the market today.
One of the strengths of GURPS, say its proponents, lies in its large number of worldbooks, describing settings from several science fiction, fantasy, and historical settings, adding specific rules but mainly giving general information for any game.
Before GURPS, Steve Jackson wrote a set of games called The Fantasy Trip, which are strongly related to GURPS.
A weekly online magazine devoted to supporting GURPS is Pyramid Magazine.