This refers to playing a poker game where the chips do not represent real money. Nothing of any value is won or lost in this type of game, so it is not considered gambling. All major online poker rooms have play money games.
When playing online poker, a fake currency can be used to allow players to play poker online without needing to deposit any of their own money.
Playing for fun or fake money. Usually online poker sites have free games with play money. This allows players to practice without wagering real dollars. Most online casinos and online poker rooms have "play money" games.