Definitions can vary from tournament Director to tournament Director, but for those three this is what I would expect…
The side pot will likely take the place of a calcutta. Anybody can contribute to it usually for a fixed dollar amount like $20 will be eligible for a payout. The money collected will go into the payout and the payout will be spread across a percentage of the field. Perhaps as high as the top 25% with the winner getting the largest share, then second place, third place and so on and so on…
Winner takes all is another separate optional pot. It's exactly what it sounds like. You throw in your $20 and whoever actually wins the tournament wins the entire pot assuming that they were contributor to the pot.
Likewise most wins. Whoever has the most individual games won throughout the course of the tournament gets this pot if they were a participant in the pot. This is usually reserved for double elimination tournaments and benefits those get sent over to the losers side early on as they have to play more games to get to the point where they may be able to win the tournament. You can actually win this pot without doing particularly well in the overall tournament.
In all cases, only those who contribute to the pot are eligible to win it. If somebody contributed to the winner take all pot and won the tournament, they would not receive that money. It will go to the highest placing person who did contribute to that pot.
Again there could be variations of these, but that's pretty much what you're looking at…
