Data files are derived from the *Google Web Trillion Word Corpus*, as described by [Thorsten Brants and Alex Franz](http://googleresearch.blogspot.com/2006/08/all-our-n-gram-are-belong-to-you.html), and distributed by the [Linguistic Data Consortium](http://www.ldc.upenn.edu/Catalog/CatalogEntry.jsp?catalogId=LDC2006T13). Subsets of this corpus distributed by [Peter Novig](http://norvig.com/ngrams/). Corpus editing and cleanup by Josh Kaufman.

Educational and personal/research use of this data is permitted under the LDC license, Norvig's MIT license for his contributions, and US fair use doctrine. I do not recommend using this data for commercial purposes without licensing it from the Linguistic Data Consortium.