Research: These searchers are further down the funnel than informational searchers. They’ve already decided that they want to buy a product, but they haven’t quite decided which one is best. They’re looking for more information, so product keywords usually include words such as "review", “top 10”, “comparison”. And while it may look like spam to you, a word like “cheap” can actually help turn researchers into conversions.
Now the ad servers don’t create this table themselves, they license it from another company like MaxMind or DigitalEnvoy, whose primary business is geolocation data. This is no enviable task; IP addresses themselves don’t necessarily have an obvious pattern in the way they are assigned like a telephone area code would. It’s a bit like solving a mystery, and the geolocation companies use a variety of methods to approach the problem. /injects>