Garry’s Mod is a sandbox mod for the Source Engine. Unlike normal games there aren't any predefined aims or goals. Players are given tools and are left to entertain themselves. The player is in a world where objects can be created and destroyed on demand. Where people can be created and destroyed with the click of a mouse. A world made for him. A world he made.
Used to be great, but Garry's Mod 13 has utterly ruined every aspect of the game! Saves are broken, loading times take too long, the Workshop is a mess, the UI is downright ugly, some OFFICIAL maps don't work at all, textures are broken, it's so badly optimized even some HIGH-END PCs can have trouble running it, for a while you could actually receive a VIRUS from playing Gmod 13, EVERYTHING IS RUINED! And Garry has been falsely banning people from forums who give criticism to it's awfulness. I can safely say he is one of the most dishonest game developers of all time.
DO NOT BUY! If you want the REAL Gmod experience, go download Lmod 12 here: Steamcommunity.com It recreates Garry's Mod 12 and IT ACTUALLY WORKS!