Glossary of web terms
Banner: an ad on the Web that links to an advertiser's site or a buffer page. Banners are the most common type of Web ad, and they come in a wide variety of sizes.
Buffer page: a page to which an ad message can link to simplify navigation or to narrow the focus of a message. Buffer pages are typically hosted by the Web site on which the ad is running, rather than appearing on the advertiser's site.
Button: a small ad unit on the Web. Buttons typically link to an advertiser's site or a buffer page. They are generally used for sponsorships or downloadable products.
Clicks: the number of times a user clicks a banner or other advertising unit.
Click rate: the percentage of impressions that result in clicks. Sometimes referred to as the response rate.
Conversion: shifting a visitor's response from passive viewing to action. Conversion can be as subtle as attracting users to your site, or as dramatic as convincing them to buy your product. Another example of conversion is getting users to fill out an online form.
Counter: a company that counts Web page and ad deliveries. Counters include AccessWatch and WatchWise. (For more counters, see our collection of Web advertising resources.)
CPM: cost per mille (French for thousand). CPM refers to the total cost of 1,000 visitor requests to view an ad -- in other words, the cost for 1,000 impressions.
Dynamic rotation: delivery of ads on a rotating, random basis (the opposite of hardwired). Dynamic rotation lets different users see a different ad on a given page, and allows ads to be seen in more than one place on a site. Depending on a site's technology, ads can be dynamically rotated throughout an entire site or within a given section, or can be called up as part of keyword searches. Also called dynamic delivery.
Hardwired: ads that are set in a fixed position on a particular page and delivered each time the page is delivered (the opposite of dynamic rotation).
Hit: every element of a requested page (including text, graphics, and interactive items) is counted as a hit to a server. Hits are not the preferred unit of site-traffic measurement because the number of hits per page varies widely. On average, a Web page contains six hits. See also page views.
Impressions: the number of times an ad banner is requested by site visitors' browsers--and presumably seen by the user. Guaranteed impressions are the minimum times an ad banner has the opportunity to be seen by visitors (as specified in the contract).
Page views or page deliveries: the number of times a Web page is requested. Page views, not hits, are the preferred counting method for site-traffic estimates and measurement.
Program: an ad buy, generally a certain number of impressions delivered in a specified period of time.
Response rate: the percentage of impressions that result in clicks. Also called the click rate.
Unique users: the number of different individuals who visit a site within a specific time period. To distinguish these users, Web sites must use an identifier such as a cookie.