As the popularity of affiliate programs has grown, services, such as LinkExchange, Commission Junction, BeFree, and many others, have arisen to provide centralized locations where Webmasters can pick and join affiliate programs. These services also monitor the vendors and keep them honest. They provide standardized software and interfaces to run the affiliate programs so that each new vendor does not have to re-invent the wheel when they start up an affiliate program.
As a Webmaster, you can go to one of these sites and pick out the programs you want to join. You fill out a form providing information about yourself and your Website and then you download the "banner code" to place on your site. When someone clicks on the banner from your site and buys something from the vendor, the sale is tracked and they pay you a small commission. Most provide online reporting so that you can see your how your sales are going at any time.
While these affiliate services help to promote affiliate programs for the vendors, and provide some efficiency for the Webmasters, vendors are still looking for better ways to promote their affiliates' programs and Webmasters are looking for more profitable arrangements.
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