A shootout is a type of multi-table tournament structure where the participants are divided onto separate tables and each table plays a separate single-table tournament as the first round of the tournament. The top finishers on each single table then advance to the next round, where all participants are again divided onto separate tables, which again play separate single-table tournaments. Eventually, all remaining participants end up at a single, final table which plays as a normal single-table tournament.
Players in a shootout tournament are never moved between tables during play. All single-table tournaments at one level must be completed before beginning the next level (for obvious reasons, since the winners at one level are part of the contestant pool at the next level).
In some shootouts, only the lone winner at each of the individual single-table tournaments advances to the next round in which case that winner, by definition, has the total of all chips that were in play on their table, and therefore all players at the next round start with the same number of chips. But in some shootouts, more than one player at each single-table tournament advances (e.g. top 2, or top 3), and the single-table tournaments are halted once that number of players is left. In such cases, players continue to the next level while keeping their current chipstack, though depending on the tournament rules, players may also each be awarded some fixed number of extra chips at the start of each level. Keeping your chipstack means players who accumulate chips early have an advantage in later rounds of this type of shootout tournament, as in a traditional multi-table tournament.
Depending on the individual tournament, the number of players who advance between each round may vary. Also, depending on the individual tournament, winners of early rounds may also win small cash prizes from the prize pool of the tournament, though as with any poker tournament, the bulk of the prize money is awarded to the top finishers at the final table.