Apostrophes have been around since the 16th Century. Their first job was to show where letters had been left out of a word.
A century or so later, they picked up their second use: to show ownership.
Debate over how to use apostrophes properly was first recorded in the 17th Century. They’ve been a pain ever since. They don’t have to be though. Either by (1) learning their basic uses and applying common sense, or (2) sticking this page next to your computer and following it blindly, you will never get it wrong again.
Apostrophes only do three jobs.
1. Show ownership
The apostrophe always goes straight after the person or thing doing the owning.
The dog’s breakfast means the breakfast owned by the dog.
The woman’s hair. The rock star’s spa pool. People’s paper. John’s room.
The same goes when the person or thing is a plural, like “dogs” – The apostrophe goes after the person or thing doing the owning.
The dogs’ breakfast means the breakfast owned by lots of dogs.
Men’s room means a room used by men. Children’s learning. Students’ work.
What about when the person or thing doing the owning ends in S?
The basic rule here – and this goes for a lot of questions of punctuation – is to spell it the way you would say it.
Bridget Jones’s Diary means the diary owned by Bridget Jones.
Vaughn Davis’s house means the house belonging to Vaughn Davis. It gets an extra S because that’s how we say it.
The Davises’ house means the house belonging to the Davises. It just gets an apostrophe (no extra S) – we don’t say “Davises’s house.”
2. Show a contraction
A contraction is where two commonly paired words are joined to make one word.
I will becomes I’ll
They have becomes they’ve
We are becomes we’re
3. Clarify meaning when writing about individual letters
Say you wanted to ask how many times the letter A was in a sentence (well, you never know…). “How many a’s are there?” uses an apostrophe to avoid the obvious confusion if you didn’t.
It’s always means ‘it is’.
For example: It’s Friday. It’s going to rain.
There is no other need for an apostrophe in its.
The dog licked its paws. No apostrophe.
Information from original memo circulated by Y&R Advertising Co, August 2007.
Apostrophes last updated 4 July 2011