In most cases, after you sign up, you download a small application, a bar that displays ads. You make money for the time you spend actively surfing the Web with the ad bar running. In some cases there is a limit on the amount of money you can make per month via direct surfing. You can make additional money by referring others. Details for individual programs are listed below.
Some programs offer other ways to make money.
Spedia, for example, lets you play games to earn as well, and the games are a lot better than their ad bar. But if you're online a lot, you will make enough to more than pay for your Internet connection. Referral amounts for the individual programs are listed below. So be smart and don't spam. You can earn more money if people you refer sign up and surf using the AllAdvantage ad bar.