Computers can be great at remembering things. Sometimes too great. The major search engine providers are competing to remember your search terms for the shortest possible period. Or at least that's what they are saying publicly. There seem to be loopholes in this competition for the shortest data retention, and in some cases I'm actually glad for that.The latest development came when Yahoo reduced its personal data retention to 6 months, down from 13 months. Google currently keeps the data for 9 months, and Microsoft still keeps your personally identifiable information for 18 months. There are definitely cases where the search engines can keep your data for much longer, though.

I don't mind a search engine keeping data about my searches as long as I can see the data and have some control over how long it's kept. It's useful to be able to see the results of past searches, particularly when you're trying to find something that you know you saw before but aren't able to find. I just checked my Google account and it has search results saved all the way back to October 2006. During that time, Google says I've made 10,552 searches. (Wow.)

On this very day in 2007, for example, I used Google to make several searches to determine how to repair a damaged Windows Management Instrumentation (WMI) setup. I've had to go back to those pages several times, and when I search for WMI in Google it shows me the date and time that I visited those pages in the past.

If some of those 10,552 searches are so embarrassing that I wouldn't want to risk anyone seeing them, Google gives me the ability to selectively delete a search. I can even remove the entire search history so that it can't be retrieved. There is no way that I would do that, though; this information is too valuable. Even though Microsoft keeps search data for the longest period of time, I couldn't find any way to view my search history with Live Search.

Even if I cleared out the search history associated with my Google account, it wouldn't really be gone for good. That's where the data mentioned in the New York Times article comes into play. It makes sense for search engines to keep details about search patterns; that's one way they can improve the quality of searches and track search trends. If Yahoo and Google can get by with less than a year's worth of details, then Microsoft should be able to do the same.