My colleague and I are having a friendly debate over 6th edition APA. He says we are to space twice after periods at the end of a sentence, and I say only one space is required. The APA manual recommends using 2 spaces in drafts (p. 88). Please clarify.

Question

shadowfiend · Answer

Two spaces are a vestige of typewritten text, which was monospaced, meaning each character took up the same amount of space. This meant that there was often an awkward amount of space between characters in a word, so two spaces were used to make the gap between sentences stand out more. More at http://www.slate.com/id/2281146/pagenum/all/ (the article is a bit vehement and tongue-in-cheek, be forewarned).

anonymous · Answer

Two spaces between words ended with the advent of word processing on PCs. I've read several references that acknowledge we've dropped its use. Can't point you to one, though.

anonymous · Answer

I've also been told by editors that the double-space after sentence punctuation is antiquated. They prefer 1 space, not 2. I don't have any citation for APA though.