Taken from the original slot machine concept , slots have become a popular gambling option in most casinos. When you play slots online for real money, the slot machine pays off according to the pattern of symbols displayed when the slot reels stop spinning. We look out for casinos that offer plenty of free slots, so you can spin just for fun, and great real money games if you favor the thrill of gambling. Further and no less important indicator is the presence of a jackpot.