A parlay in sports betting is when a bettor makes multiple wagers (at least two) and ties them into the same bet. If any bets in the parlay lose, then the entire parlay loses. However, if all wagers win, the bettor gets a bigger payout.
There's no question parlay's are fun, they just don't pay out pay enough to make up for the added risk. So if your goal is to make money sports betting, stick to straight bets. If your goal is to get bragging rights or the thrill of a lottery ticket, throw in some money you're willing to lose on a parlay.