"A" and "an" with acronyms and initialisms
Short forms that start with consonants don’t always follow "a."
Focus on how they’re pronounced.
If they begin with a vowel sound, use "an," as in an HTML tag and an ROI analysis.
"Setup" vs. "set up" and "login" vs. "log in"
If you’re using either as a verb, make them two words.
Set up your account before you log in.
When using them as nouns and adjectives, close them up.
You’ll receive your login name once you finish the setup.
"Online" vs. "on line"
This one’s easy. It’s always "online."
Hyphens vs. dashes
If you’re breaking up a sentence—like this one—use an em dash. (Use — as an HTML shortcut.)
Comparing numbers? Find yourself an en dash, as in 10–15. (– in HTML.)
Save the all-too-common hyphen for compound constructions and bro-
Two spaces after a period
Despite what you learned in high school, adding an extra space after periods has been verboten since the days of the monospaced typewriter.
You get one space. Deal with it.
This, and many other errors, often comes from transferring content directly to the web from tools such as Microsoft Word.
You probably don’t want to do that, either.
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