There are five players on the arena at any time, goalie included. Unlimited substitutions are allowed, which means players go all-out for their entire shift before they sub off.
Because the ball doesn't bounce and is harder than a regular soccer ball, it stays close to the ground for essentially the entire game until somebody shoots it!
Futsal is a fantastic game, and because it is sanctioned by FIFA, there are many tournaments and competitions.
North American indoor soccer is really distinct from Futsal. Firstly, it is typically played on turf rather than a hard surface. It's also played with a regular outdoor ball. These two combine to make it much more like outdoor soccer than Futsal is.
The court is usually larger than a Futsal field, and more importantly, there are walls on the sides of the arena. You can play the ball off these walls, which adds a new part to the game.
North American indoor, while still focused on passing, also has a lot of dribbling, especially on the sidelines. Since defenders cannot force the attackers out of bounds (because of the walls), the attackers are more likely to attempt to dribble past their defender.
North American indoor adds a whole new part to the game, which includes lots of different strategy as well. It is interesting to some people and not others, so definitely go watch a game before you sign up!
European indoor soccer is very similar to North American soccer, so this is a shorter section.
European indoor soccer fields are essentially the same as North American indoor soccer arenas. The difference is that in European indoor, they use a Futsal ball instead. This makes an interesting dynamic where there is more passing than in North American indoor soccer, because the ball is harder to dribble.
