Paul Brians, Professor of English at Washington State University, has compiled a list of “Common Errors in English.” It includes such oldies as “the principal is your pal” and new gems such as “PIN number”. He states that the term “‘PIN’ was invented to meet the objection that a ‘password’ consisting of nothing but numbers is not a word.” I thought it was a clever marketing gimmick. He also has a list of non-errors, which is just as handy as the errors. (thank you Kathryn!)