Free spins are a bonus feature in slot games that allow you to spin the reels a set number of times without placing additional bets, while still having the chance to win real payouts.
They are usually triggered by scatter symbols or bonus rounds, and may include additional features such as multipliers or expanding wilds depending on the game. In some cases, free spins can also be awarded as a promotional or in-game bonus, which players can then use on a specific eligible slot.
The exact rules and conditions for free spins vary by game and provider, and can be viewed in the information section within the slot window.