Apparently, everyone knows that tf-idf stands for "term frequency-inverse document frequency". I had no idea, and the article didn't have time to include a link

Apparently, everyone knows that tf-idf stands for "term frequency-inverse document frequency". I had no idea, and the article didn't have time to include a link to http://en.wikipedia.org/wiki/Tf%E2%80%93idf http://en.wikipedia.org/wiki/Tf%E2%80%93idf or even type out the acronym.