What search terms are trending in Google?
How many times did users google “Lumix” (Panasonic camera line) in the last 5 years?
Or “Greek debt crisis” in the last 12 months?

Google Trends allows you to explore popular searches from 2009 and onwards. Google Trends tables and graphs are based on an analysis of subsets of Google web searches with a view to determining how many searches have been carried out for the terms you have entered. Because the Google search engine has become the mastodon that it is, this analysis can help you understand exactly how interesting various topics are in specific world communities or geographies.

All graphs and images may be used in teaching materials as long as you credit the source.

If you are interested in knowing how the graphs have come about, you will find more information in the Google Trends help file.
Click to view the Lumix example.