What does it mean to buy a coupon on Groupon?

Groupon offers one "Groupon" per day in each of the markets it serves. If a certain number of people sign up for the offer, then the deal becomes available to all. If the predetermined minimum is not met, no one gets the deal that day. This reduces risk for retailers. Groupon makes money by keeping approximately half the money the customer pays for the coupon.

For example, if you purchase Groupon for $100 for a restaurant for $50 through Groupon.com, then the business gets $25 and Groupon keeps $25. You get to spend $100 at the restaurant using the Groupon that you paid $50 for, saving you $50 at that restaurant.