We learn new things everyday. As english is not my mother language, I couldn’t have guessed this one if I weren’t told of it. For years, I’ve been using the REFERER http header in my web projects like everyone, and of course for me there was no reason to think it was not the right spelling for it. But it is. And modern spellcheckers have it in their database: the correct spelling is REFERRER with two Rs.
Where and when does this mistake come from?
The mistake comes from 1996 actually, in RFC 1945, the document that gives the specifications of the HTTP1/0 protocol. It was at first a misspelling in the computer scientist Phillip Hallam-Baker’s original proposal to include the field to the HTTP specifications. At this period, neither REFERER or REFERRER were recognized by the standard unix spell checker, and the misspelling remained. (wikipedia, 2009) <= hehe the Harvard referencing system is now in my blood 🙂
Referer with only one R is now a word commonly used by professionals in the domain, and we might be able to write both without passing for a fool (you’ll even pass for an erudite person when you explain the origin of the word to your colleagues during the coffee pause)
Notice that the correct spelling, referrer, is also in use in some contexts, such as the DOM specifications (document.referrer).