Lets you keep more than one tournament going at once (e.g. two class periods running their own bracket).
One per line, or separated by commas. Byes are added automatically if the count isn't a power of 2.
Double elimination adds a losers bracket — a team isn't out until it loses twice. Round robin plays everybody against everybody, no eliminations. Pools splits entrants into round-robin groups that feed an elimination bracket. Swiss pairs similar records for a fixed number of rounds — nobody is out after one loss.
Random shuffles the list. As entered keeps your list order (also used for byes). Ranked treats your list as seed 1..N in order and places seeds so the top two can't meet before the final — seed 1 plays the lowest seed in round 1. Round robin only affects the standings table's Seed column. Pools uses it to order entrants before splitting into pools; Swiss uses it for round 1's pairing and its standings' Seed column.