Search Networks
In the world of paid search there are 4 main search networks which account for approximately 98% of the market. These are Google, Yahoo, Baidu & Bing.

The paid search networks are often confused with the search engines themselves; however, they are actually two separate things. Often the paid search networks will have their own search engines e.g. Google, Yahoo, Bing etc...,however, they also have a network of affiliated partner sites which display their paid results alongside the search engines own organic listings e.g. AOL, ASK, Lycos etc...
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