Online Advertising

CPC (Cost Per Click) or PPC (Pay per click) is when advertisers pay each time a user clicks on their listing and is redirected to their website. They do not actually pay for the listing, but only when the listing is clicked on. This system allows advertising specialists to refine searches and gain information about their market. Under the Pay per click pricing system, advertisers pay for the right to be listed under a series of target rich words that direct relevant traffic to their website, and pay only when someone clicks on their listing which links directly to their website. CPC differs from CPV in that each click is paid for regardless of whether the user makes it to the target site.
CPA (Cost Per Action or Cost Per Acquisition) or PPF (Pay Per Performance) advertising is performance based and is common in the affiliate marketing sector of the business. In this payment scheme, the publisher takes all the risk of running the ad, and the advertiser pays only for the amount of users who complete a transaction, such as a purchase or sign-up. This model ignores any inefficiency in the sellers web site conversion funnel. The following are common variants of CPA:
CPL (Cost Per Lead) advertising is identical to CPA advertising and is based on the user completing a form, registering for a newsletter or some other action that the merchant feels will lead to a sale.
CPS (Cost Per Sale), PPS (Pay Per Sale), or CPO (Cost Per Order) advertising is based on each time a sale is made.
CPE (Cost Per Engagement) is a form of Cost Per Action pricing first introduced in March 2008. Differing from cost-per-impression or cost-per-click models, a CPE model means advertising impressions are free and advertisers pay only when a user engages with their specific ad unit. Engagement is defined as a user interacting with an ad in any number of ways.
Cost per conversion Describes the cost of acquiring a customer, typically calculated by dividing the total cost of an ad campaign by the number of conversions. The definition of "Conversion" varies depending on the situation: it is sometimes considered to be a lead, a sale, or a purchase

Types:
for as long as the website exists with no extra costs.

Floating ad: An ad which moves across the user's screen or floats above the content.
Expanding ad: An ad which changes size and which may alter the contents of the webpage.
Polite ad: A method by which a large ad will be downloaded in smaller pieces to minimize the disruption of the content being viewed
Wallpaper ad: An ad which changes the background of the page being viewed.
Trick banner: A banner ad that looks like a dialog box with buttons. It simulates an error message or an alert.
Pop-up: A new window which opens in front of the current one, displaying an advertisement, or entire webpage.
Pop-under: Similar to a Pop-Up except that the window is loaded or sent behind the current window so that the user does not see it until they close one or more active windows.
Video ad: similar to a banner ad, except that instead of a static or animated image, actual moving video clips are displayed. This is the kind of advertising most prominent in television, and many advertisers will use the same clips for both television and online advertising.
Map ad: text or graphics linked from, and appearing in or over, a location on an electronic map such as on Google Maps.
Mobile ad: an SMS text or multi-media message sent to a cell phone.
Superstitial: An animated adv on a Web page from Enliven Marketing Technologies. It uses video, 3D content or Flash to provide a TV-like advertisement. Used to be known as Unicast Transitional ads as they were originally made by Unicast Communications but the company was acquired by Viewpoint Corporation in 2004, which then changed its name to Enliven in 2008.
Interstitial ad: a full-page ad that appears before a user reaches their original destination.
In addition, ads containing streaming video or streaming audio are becoming very popular with advertisers.