[Headline appropriated from i love typography]
An apostrophe is the same character as a closing single quotation mark.
Blame the “backwards” apostrophe on applications like Microsoft word that use an opening single quote where a word or term begins with an apostrophe, like ’til or ’60s. The software incorrectly interprets the character as the start of a quotation. You will have to manually fix this. And when you do, the typographic gods will smile upon you.
Use an apostrophe for contractions, REGARDLESS of where in the word the missing letters fall.
Using an apostrophe incorrectly can have dire consequences: