A Shootout poker tournament is a sole, sequential event.
Although it has a more rigid structure, a Shootout poker tournament is similar to a Step tournament. The major difference is that at a Shootout tournament, you can either win or lose. You can't get a seat to a lower step or the same step, nor can you gain entry into the poker tournament in any step other than the first.
Shootout poker tournaments have varying structures and qualifications. While some Shootouts may award just one seat to the following round per table, others award several seats.
The prize pool at a Shootout poker tournament is usually divided among the individual table finishers, a prize structure that online poker players favor. Even though the absolute final first place winner will get much more than the other players, shootouts are ordinarily structured in a manner that enables all the final table players to get a part of the buy-ins.
Michael Orwell - Editorial Board