It’s not a single game, but rather a collection of more than 50m games, all created by its community of players.
It has flown more under the media radar than those rivals, leaving parents whose children are now asking to play it (or playing it without asking) in need of a primer.
Roblox may not be as famous a children’s game as Fortnite or Minecraft, but it recently announced that it has more than 100 million active monthly players.