Roblox is a free Lego style Multiplayer game, where you play in user-created worlds with blocks. Unlike most other games there aren't any pre-defined goals. You are given a variety of objects, a scripting language, other people and left to do whatever you want. With your free account, you get a Character and a Place. You can customize your place and character however you want, and visit anyone else's place as well.

Roblox is a massively multiplayer online game (MMOG) virtual playground and workshop designed, like second life meets lego. Players can design and create their own worlds and items while interacting with other players. Different games have different goals and elements of fun. Most of them have a little player vs player action while you complete your other goals.