I was driving down Ventura Blvd. in Studio City, California, the other day when I saw this sign in the window of a hair salon:
Walk-in’s Welcome
Hmm. What’s that apostrophe doing there? Shouldn’t the sign read Walk-ins Welcome? I think so, if the message is that people without appointments are welcome. Of course, if the sign was meant to announce a welcome for a walk-in customer, then it’s fine as it is. My guess? Whoever approved the sign had spent too much time under the hair dryer.
What this sign needs is a plural noun—walk-ins. The message is that walk-ins are welcome at this salon. But the apostrophe turns the plural noun into the possessive form. Except in a couple of very specific situations (see #4 and #5 below), the apostrophe is not used to form the plural of a noun.
So for the folks at the salon and anyone else who needs it, here’s a quick review of the uses of the apostrophe:
1. To show possession
·      Greta’s Salon
·      the prince’s palace
2. In contractions to show that letters are missing
·      I’ve (I have)
·      haven’t (have not)
3. In dates to show the century number has been eliminated
·      ’80s disco music
·      the Spirit of ’76
4. To make the plural of certain forms of letters, abbreviations, and figures
·      dot your i’s and cross your t’s
·      Ph.D.’s
·      1990’s (or 1990s)
5. To avoid confusion
·      too many which’s and that’s
Let’s hope the folks at that Studio
City salon are a bit more skilled at hair than at signs.