Internet Marketing Glossary
CPM or Cost Per Thousand - The "cost per thousand" is the cost of the ad per thousand impressions delivered.  A $50 CPM means that the advertiser will pay $50 for every thousand impressions, or ads delivered.

CPC, CPT & CPA (Cost Per Click, Cost Per Transaction and Cost Per Action) - All of these terms represent various forms of paying for the performance of a ad banner campaign. When an advertiser places a buy as a cost per click, they agree to pay a fixed amount (say 25¢) for every click to their URL (such as GoTo.com). When an advertiser places a buy as a cost per transaction or cost per action, they agree to pay a fixed amount (say $5.00) for every action or transaction received from a site (such as Travelocity) when visitors interact with their banner. 

CTR or Click Through Rate - A ratio of the number of times users have clicked on an ad banner as a percentage of all ad banners delivered. This ratio indicates the success of the banner in attracting people to click on it to view more information. 

Keyword - A word or phrase entered by the user to request specific information. Keywords usually include destination cities, origin cities, region, country, state and city.

GIF File Format - The full name of this file format is Compuserve Graphic Image Format, but most people on the Web know it as GIF, the most common graphic file type used to build web sites and banner ads. GIF files can be viewed on a web browser as a static graphic, or in the form of a GIF89 image, which allows them to be animated.  Animated GIFs simply rotate one GIF and then another.

Link or Hyperlink - Text or graphics on a web page which, when clicked on, transferd information to your web browser. When you click on an ad banner, you link to the information in the banner address, which is typically the advertiser’s web page.

Page Views or Impressions - The number of times a reader sees the sponsor's banner image. This is a more advertiser-friendly way of determining exposure for an advertisement. Each page delivered represents one page view or one impression.