Google Books Ngram Viewer

The Google Books Ngram Viewer, which Google created with the Encyclopedia Britannica and scientists from Harvard and the Massachusetts Institute of Technology, takes 500 billion words from 5.2 million digitized books and allows you to track their usage over time. The result is a database that shows when certain phrases, people, ideas and trends faded in and out of fashion, and gives the results in an easy to interpret graph. Best of all, the database has been licensed under a Creative Commons Attribution license, meaning the results are free for you to use, as long as you include an attribution to Google. The datasets Google uses can also be downloaded and used under the same CC license.

The ngram viewer is here: http://ngrams.googlelabs.com/

Here's how it works: you type in one or more words or phrases, separating them with commas, hit Enter, and the viewer returns a color-keyed graph of the number of mentions of those words or phrases from Google Books entire database of text.

Here's a screenshot of the number of occurrences of two words - "religion" in blue, and "television" in red - over the Google books database of all English text works between 1800 and 2010. The results are not scientific, in that you have little control over which books Google has or hasn't indexed. But they're pretty interesting.



More information about the ngram viewer is available at http://ngrams.googlelabs.com/info