A Free Play is a bonus play that allows you to place a bet without any risk. For example, if you place aR$55 real money wager at -110 odds, this will be riskingR$55 to winR$50. However, with aR$55 Free Play, there is zero risk so this becomesR$0 to winR$50. If you lose, there is no change to your real money balance.
With 10 spins at 50 cents each, I don't seem to win anything. As soon I put my money in, the machine seems to change and starts to pay with some credits.  Gerry L. ANSWER: More and more casinos are rewarding slot players with free play, giving them a chance to win without having to drop a dime into a machine.