Just like how water has no shape and the wind is invisible, so can ROBLOX take on all different kinds of forms. You could make a birthing simulator, or a 15FPS FPS...
...Philosophical nonsense.
ROBLOX is a game that allows you to make games yourself; all you need is lua. Presumably. I believe the primary demographic is children, but JoJo fans and protogens like to play it, too. Not what I'd expect.
Over 4 billion(???) accounts have been registered on ROBLOX (One third of them are probably bots), and the most popular games — named "Experiences", but I refuse to call them that — on the platform tend to have a daily player count in the 10k range. Whether or not these games interest you depends on your tastes.
Of course, chances are most of the "experiences" on the front page won't interest you. Like, at all. So, uh, have fun?
Things you can do in ROBLOX:
Currently, no reviews are in the making. Sonic is dead.
I judge games not only by their quality, but also if they are fun to play. Thus, bad games that are fun get a better rating than games that bore me to death.
To developers of games I reviewed: These reviews are not meant to insult you, the creator. I try to state my honest opinion about your game. Criticism is important, for it helps us get old and wise. But in the end, it might just be me and my preferences. You might disagree with me and say your game is fine... And that's OK. You don't have to listen to me; as long as your players are happy with your game, you don't have to change the game. Just because I don't like it, doesn't mean no one likes it. Please don't take it to heart. I love you!