"An advertising network (also called an online advertising network) is a service that was born out of the needs of the market.A network representing many Web sites in selling advertising, allowing advertising buyers to reach broad audiences relatively easily through run-of-category and run-of-network buys.
Advertising networks provide a way for media buyers to coordinate ad campaigns across dozens, hundreds, or even thousands of sites in an efficient manner. The campaigns often involve running ads over a category (run-of-category) or an entire network (run-of-network). Ad networks vary in size and focus. Large ad networks may require premium brands and millions of impressions per month.
Small ad networks may accept unbranded sites with thousands of impressions per month.An advertising network is an online net where many different companies advertise their product. The idea is similar to the multi-product catalogs that were very common 10 to 20 years ago. The difference between an online ad network and a physical catalogue is that the former reaches an online audience: it is available 24 hours a day, 7 days a week, and it can be updated with new information on products and promotions.
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