How Many Spaces Go After a Period

Put just one space after a period. If you grew up using a typewriter, you were probably taught to put two spaces after a period (a practice called English spacing). But like the typewriter itself, that custom went out of fashion many years ago. With modern word-processing programs, a second space is not only inefficient (requiring an extra keystroke for each sentence) but potentially troublesome: it can cause problems with line breaks. In most cases, computers use proportional fonts so that a single keystroke creates the proper space between sentences. (When youre writing online, youll find that many computer programs wont even recognize a second space.) In addition, theres no evidence that an extra space makes a document any easier to read. Of course, if youre still using a typewriter, feel free to continue putting two spaces after a period. (And dont forget to change the ribbon now and then.) Postscript: Spacing After Other Marks of Punctuation As a general rule, put one space after a period,  comma, colon, semicolon, question mark, or  exclamation point. But if a closing quotation mark immediately follows any one of these marks, dont insert a space between  the two marks. Heres how that looks in American English: John said he was tired. Mary said she was knackered. I said I was hungry. In British English, as a general rule,  knackered would be in single quotes (inverted commas) and the period would follow the closing quotation mark: Mary said she was knackered. In either case, dont insert a space between the period and the closing quotation mark. Spacing around the dash [or em dash] varies, according to Merriam-Websters Manual for Writers and Editors. Most newspapers insert a space before and after the  dash; many popular magazines do the same, but most books and journals omit  spacing. So choose one way or the other, and then be consistent throughout your text.