There's no excuse for double spacing.

In the issue of professionalism, consistency and the good of humanity, I give you the following announcement: Enough with the double spaces after periods already. Please.

I know many of you double spacers feel you are in the right and want to continue your antiquated method of typing because you were taught this as a rule. However, this has been outdated for some time now, and you must let it go.

I understand your reluctance. Because I was also taught to double space. But I should add I was taught on a TYPEWRITER, which is the only reason one would ever need to double space in the first place. It was also the 90s. I don’t want to let the 90s go either. I still have flannel shirts from that decade that I want to wear today. But like those shirts, the double spacing simply does not fit anymore.

Reasons why:

1. This is not an issue of preference or taste. This is a rule, and if you double space it is an error.

Every major style manual (including the AP Stylebook,the Chicago Manual of Style, and the Modern Language Association) makes it clear that one space is proper.

2. We used to double space on typewriters. It does nothing to improve readability on word processors or computers.

From Mignon Fogerty (a.k.a the Grammer Girl):

Most typewriter fonts are what are called monospaced fonts. That means every character takes up the same amount of space. An "i" takes up as much space as an "m," for example. When using a monospaced font, where everything is the same width, it makes sense to type two spaces after a period at the end of a sentence to create a visual break. For that reason, people who learned to type on a typewriter were taught to put two spaces after a period at the end of a sentence.

But when you're typing on a computer, most fonts are proportional fonts, which means that characters are different widths. An "i" is more narrow than an "m," for example, and putting extra space between sentences doesn't do anything to improve readability.

3. Somebody has to clean that stuff up.

Those of you who want to continue to double space should know that copy-editors or art directors have to go in and take out all those spaces. When putting documents that have been piecemealed by multiple writers – some are double-spacers others are not – we can’t let some double spaces go and others stay. So, in the interest of consistency, those spaces have to be taken out.

It’s like dropping trash on the floor and then walking away. Someone has to deal with that later. I changed (in 1994), and so can you.

Thank you, Bret

Additional sources: http://grammar.quickanddirtytips.com/spaces-period-end-of-sentence.aspx http://www.wewriteforyou.com/Blog/?tag=ap-stylebook