Affiliates were among the earliest adopters of pay per click advertising when the first pay-per-click search engines emerged during the end of the 1990s. Later in 2000 Google launched its pay per click service, Google AdWords, which is responsible for the widespread use and acceptance of pay per click as an advertising channel. An increasing number of merchants engaged in pay per click advertising, either directly or via a search marketing agency, and realized that this space was already occupied by their affiliates. Although this situation alone created advertising channel conflicts and debates between advertisers and affiliates, the largest issue concerned affiliates bidding on advertisers names, brands, and trademarks. Several advertisers began to adjust their affiliate program terms to prohibit their affiliates from bidding on those type of keywords. Some advertisers, however, did and still do embrace this behavior, going so far as to allow, or even encourage, affiliates to bid on any term, including the advertiser's trademarks.
In the case of cost per mille/click, the publisher is not concerned about whether a visitor is a member of the audience that the advertiser tries to attract and is able to convert, because at this point the publisher has already earned his commission. This leaves the greater, and, in case of cost per mille, the full risk and loss (if the visitor cannot be converted) to the advertiser.
ClickBank aims to serve as a connection between digital content creators (also known as vendors) and affiliate marketers, who then promote them to consumers. ClickBank’s technology aids in payments, tax calculations and a variety of customer service tasks. Through its affiliate network, ClickBank also assists in building visibility and revenue-generating opportunities for time-strapped entrepreneurs.
When promoting affiliate offers, just make sure you are fully aware of all the terms and conditions attached to your affiliate program. Some programs can be strict about how they allow you to promote their products. For example, some may limit you to banner ads and links only, while others will allow you to use paid advertising, but won't allow email marketing.