(keep in mind, this is just my opinion!)
Believe me, I played Roblox for 3 years now. What I can tell for sure is that people seem to have VERY different opinions on Roblox. (Some people hate it, some people can't survive without it.) And I'm one of those people that can't survive without it. There are over 40 million games created by users on Roblox, so if you decide to play you might find one that you actually will spend time of your life playing. You can also customize your avatar, create groups, make games, etc. So yeah you get the basic idea. But what I love most about Roblox isn't about what I just listed. I love Roblox because of how many friends I made! The first thing I do after school is hang out, chat, play games with my friends on Roblox.
Roblox is really the best game that I ever found.
Hey, if I hadn't I'll be bored all the time.
So yeah, if you don't play Roblox I'd recommend joining.