Advertising network refers to an infomediary, which serves between a group (network) of web sites (which want to host advertisements) and advertisers which want to run advertisements on those sites. Increasingly Ad networks are companies that pay software developers as well as web sites money for allowing their ads to be shown when people use their software or visit their sites.
Ad networks serve advertising on your website and share advertiser revenue for qualified clicks each time your site's visitors click on ads. An advertising network (also called an online advertising network or ad network) is a collection of (often unrelated) online advertising inventory. When it is clear that the environment involved is the Internet, companies who run or administrate such networks are also called Advertising Agents or simply Agents.
Online advertising inventory comes in many different forms. This inventory can be found on websites, in RSS feeds, on blogs, in instant messaging applications, in adware, in e-mails, and on other sources. Some examples of advertising inventory include: banner ads, rich media, text links, and e-mails. (This is not an exhaustive list.)
An advertiser can buy a run of network package, or a run of category package within the network. The advertising network serves advertisements from its ad server, which responds to a site once a page is called. A snippet of code is called from the ad server, that represents the advertising banner.
Large publishers often sell only their remnant inventory through ad networks. Typical numbers range from 10% to 60% of total inventory being remnant and sold through advertising networks.
