Section 5.1. CPC Terminology

5.1. 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.

Click

Occurs when a site visitor to your web page clicks on a link in an ad unit. Not all clicks generate revenue (for example, fraudulent clicks that are detected and clicks on public service ads don't pay you anything).

Click fraud

A click made without actual interest in the product or services offered. For example, clicks by a site publisher on the ads on a site or on the ads of a competitor (to jack up advertising costs for the competitor).

Click through rate (CTR)

The number of clicks an ad unit receives divided by the number of times it is shown.

Effective cost per thousand impressions (eCPM)

eCPM is a way to compare revenue from different kinds of advertising. eCPM is calculated by dividing the total earnings from an ad by its impressions in thousands. You can use this calculation to compare CPC revenue with its eCPM equivalent and decide which represents a better revenue opportunity.

For more on CPM, see the "CPM Advertising" box in this chapter.

Impression

Short for ad impression; the number of times an ad is displayed.

Page CTR

The CTR for an individual web page.

Page eCPM

The eCPM for an individual web page.

Page impressions

The number of times an ad unit is displayed.

Public service ad (PSA)

Public service ads are often served before relevant content has been specifically targeted.