Chapter 5. CPC Advertising

CPC—cost per click—advertising is the most common way to make money by accepting ads on your site. With CPC, an advertiser pays a fee when someone clicks its link on your site, and you get a portion of that fee. CPC ads are mostly (although they don’t have to be) text-only.

The idea of making ads contextual—that is, relevant to the content of the web page near the ad—is closely bound up with CPC advertising. CPC ads that are contextual are much more effective, and generate more revenue for a site owner, than ads that are not contextual. But, it is worth bearing in mind that you can have CPC ads that are not contextual, and, conversely, contextual ads that pay on some other basis than CPC.


Affiliate advertising—where a visitor to your site clicks on a merchant’s link, and you get paid when the visitor actually buys something from the merchant—is explained in Chapter 4.

CPC Terminology

When you first start working with a CPC program as a web site publisher, you will encounter some terms that may not be familiar to you. These concepts are actually pretty straightforward, so it makes sense to start a discussion of CPC by looking at the definitions of the most important terms you may not know or may mean something that is slightly different than in normal usage:

Ad unit

A group of ads displayed by a single call to the server’s script, usually from one to six text-only contextual ads.


Occurs when a site visitor to your web page clicks on a link in an ...

Get Google Advertising Tools now with O’Reilly online learning.

O’Reilly members experience live online training, plus books, videos, and digital content from 200+ publishers.