What is an apostrophe?
Apostrophes are those little floating comma shapes that denote contractions and possessives, and that sometimes even make words plural. They’re tiny, they’re tricky, and yes, the way you use (or misuse) them instantly indicates your grade in high school English. As the famously nitpicking former editor Lynne Truss once put it, “To those who care about punctuation, a sentence such as ‘Thank God its Friday’ (without the apostrophe) rouses feelings not only of despair but of violence.”
Do use apostrophes for contractions
Where do apostrophes come from, anyway? The more informally we speak, the more often we tend to leave out letters and even small words. Our brains glide over these small omissions in the spoken word, filling in the blanks, but when it comes to writing, we still use apostrophes to indicate that something has dropped out. For example, the apostrophe in isn’t points to the missing o in not. Someday it may be acceptable to write isnt in a business letter, but at this point, it still is not a great idea.
Do use apostrophes to show possession
Of course, apostrophes don’t only serve as place holders for missing letters or words – they also indicate possession. Take this easy example: In “the king’s book,” the book belongs to the king. Some scholars believe the possessive apostrophe was introduced in the 17th century as another form of contraction, with the full, more formal expression being “the king his book.” Why didn’t “the queen her book” turn into “the queen’r book”? No one knows, but the male ending might have been given bigger importance than the female ending.