Advertising network

From SEO Wiki

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 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.)

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.

Smaller publishers often sell all of their inventory through ad networks. One type of ad network, known as a blind network, is such that advertisers place ads, but do not know the exact places where their ads are being placed.

In most cases, ad networks deliver their content through the use of a central ad server.