brackets is how many consecutive wins are required in order to win the tournament.. if you have a 1v1 tournament with 1 bracket, it is 1 1v1 game.. 2 brackets, is 2 1v1 games, of which the winners play each other.. 3 brackets is 4 1v1 games, the winners play each other, and then the winners of those once again play each other to determine an end tourney winner.

this is an 8 bracket tourney

http://warlight.net/MultiPlayer.aspx?TournamentID=1235
the amount of players that can play is decided by the number of brackets and the size of the teams/number of teams