What does "free roll" mean in poker and how does it impact gameplay?

In Poker, a "free roll" refers to a situation where a player has the opportunity to win a pot without risking any additional money. This can happen when a player has a hand that is already guaranteed to win or tie with another player's hand. A free roll can impact gameplay by giving a player a chance to win more chips without the risk of losing any, potentially changing the dynamics of the game and influencing betting strategies.