Each year since 2001, Google releases its Zeitgeist summary, showing various lists of top search terms. By examining these lists, we can figure out something about the year -- or at least about the people who use Google to search during that year. For example, this year (so far), here are the "Fastest Rising" search terms:

1. chatroulette
2. ipad
3. justin bieber
4. nicki minaj
5. friv
6. myxer
7. katy perry
8. twitter
9. gamezer
10. facebook

Personally, I don't even know what #4, 5, 6, or 9 are. (Perhaps I should Google them.) And I wish I didn't know what #1, 3, or 7 were. Similar insights come from the "Fastest Falling" list, showing terms that were popular in 2009 but have fallen quickly. I feel a bit wistful looking at these search terms of yore:

1. swine flu
2. wamu
3. new moon
4. mininova
5. susan boyle
6. slumdog millionaire
7. circuit city
8. myspace layouts
9. michael jackson
10. national city bank

Oh New Moon, we hardly knew ye.

Google even has a surprisingly touching video showing the year in search:

Sure, it's part Google promo video (with lots of YouTube clips, Google search, Google Earth, and Google Voice shots finding their way in). But it's also a uniquely technological way to look at the year that was. (It is worth clicking through to the site, as there are interactive graphs showing trends over time, trends by region, and so on. My favorite is the United States view, "People: Music." How is it that I don't own an album by any of these artists?)

Earlier years can be viewed here.