Kevin Bankston & Markham Erickson:

Search queries are stored and used by Internet companies for internal purposes. Unfortunately, AOL made a mistake in publishing its subscribers’ online search requests. This should not have happened, and I hope every Internet company is evaluating its information procedures and policies to ensure that kind of thing does not happen again.

There are good, legitimate reasons why an Internet company would use historical search queries for internal uses. For example, search query information can be used in research and development to make improvements to search technology, to better tailor and make more efficient users’ online requests. Companies also analyze historical query information to detect and protect against click fraud — an activity that involves faking clicks on Web advertisements to drive up costs.