Just one space, please
I thought most people knew this already.
In the “Maxims for editors” post, I reminded readers, “Don’t type two spaces after a period.” Now I’m hearing from people who wonder why. It’s simple. When people used typewriters (Little Ones, ask Gramps to tell you about typewriters), they were taught to type two spaces after a period to make clear where sentences ended and began. That is because typewriters used monotype fonts, in which each character took up as much space as any other.
Word-processing programs, like those used by newspapers, magazines, and book publishers, use proportional fonts—an m takes up more space than an i. With proportional fonts, the additional space after a period is unnecessary. This has been endorsed by The Chicago Manual of Style. In fact, editors preparing texts for publication have to take the trouble of excising the additional spaces after periods if you persist in inserting them.
Unless you are still using an Underwood or a Remington, it’s time you broke yourself of the habit.