The most striking difference between the versions is that on the PC, the player can choose whether to play the game at noon or dusk (later GTA games would feature an in-game clock which changes the scenery as time goes on).
Unlike later entries in the series, Grand Theft Auto 2 was originally designed as a Windows PC game, before being ported to the PlayStation and Dreamcast (and in a simplified form for the Game Boy Color). The PC version of Grand Theft Auto 2 was re-released under a freeware license in 2004. While GTA 2 has three maps (like the first game), all take place in the same city. There are more NPCs in GTA 2 than its predecessor, as well as computer-controlled car thieves and pickpockets. Balancing the three gangs and completing all the missions lets the player move onto the next district. If it's too low, they'll be shot at until the player murders members of rival gangs (which in turn reduces their respect meter).
If the player has enough respect, they can continue taking on missions. Each of the three maps ("districts" or "sectors") has regions controlled by one of three gangs, and the player works for all three in order to earn "respect", indicated by three separate meters in the HUD. GTA 2 was the first in the series to introduce the concept of "gangs". It was seen to be as controversial as the previous titles as a result. Like its predecessor, the game allows you to hijack any car on the map and kill anyone who gets in your way. GTA 2 follows the player as a criminal named Claude Speed walking the streets of "Anywhere, USA".