Q: what is crack with it? (Iv never been to a live event before)

A: Basically exactly as you see on TV, however its for fun from the roboteers perspective and the general entertainment of the audience.

Q: what weight classes are there?

A: Usually Heavyweights and Featherweights

Q: iv read some things that spinners are band for some reason in some tournaments. Why? And is this one?

A: Read the FRA rules and find out the grade of the arena your intending to visit. Grade 3 are limited to 500rpm due to safety as higher Grade arenas are incredibly expensive.