If somebody places an all-in bet in the game and other players continue to place higher bets, the pot will be split between players, if the main winner will be the player with a lower bet.
To explain extra pots in poker, let's use an example.
Let's say you're playing with two other players and you all go all in.
You have 5,000 chips, and other players have 40,000 chips. If you win, you can only claim an amount equal to your bet, so you get 15,000 for winning – 5,000 from each player. The remaining players then compete with each other for the remaining chips. This is how a pot is split among several players.