Definition of pot exterior
The outer pot is identified in English as "side pot". An outside pot is created in addition to the main pot when one or more players are all-in and the other players still have chips in their hand. Only players who are still in the hand after the pot Outer pot is created will be entitled to the 2 pots. For example, if 3 players are all-in, player number 1 with €1000, player number 2 with €1000 and player number 3 with €100, the total pot will be €pot00 with a main pot and an outside pot and it is obvious that even if player number 3 has the best hand, he will not win the whole pot.
Pot outside, a specific example
Let's go back to our example above and give more details. Player number 1 is button with a stack of 1000€, player number 2 is small blnd with a stack of 1000€ and player number 3 is small blnd with a stack of 100€. All blnds are €5/€10. Button opens at €side pot, small blnd call and big blnd pushes to €100 stack. Button calls and small blnd also calls. Here the pot is €300. This pot will be the main pot. This is the only pot that player number 3 will be entitled to. The action at the flop is check-checked, just like on the turn. At the river, the button bets big0€ and the small blnd calls. This €400 (€big0 + €big0) will be the outside pot that only players number 1 and 2 will be allowed to play. Player number 3 will win the main pot only, if he has the best hand of the 3 players.