The process of a visitor clicking on a Web advertisement and going to the advertiser's Web site. Also called ad clicks or requests. The click rate measures the amount of times an ad is clicked versus the amount of times it's viewed.
See "How Affiliate Marketing Works" in the "Did You Know..." section of Webopedia.
Also see Refer-It.com, a directory of referral & affiliate programs for e-commerce, featuring information on over 6,500 affiliate programs.