Grammar Lesson of the Week

I was an English major in college.  Therefore, grammar (and its brother, correct spelling) are very important to me.  Recently, I was reminded of one of my biggest pet peeves when it comes to grammar:  the possessive apostrophe.  It is a relatively simple rule, but I believe it is mystifying to many, many people.

When showing a possessive form of a singular noun, it is proper to use an apostrophe before the "s". 

Examples:

Michael's car (not Michaels car, or Michaels' car)
a hard day's work
the basket's handle

NEVER, NEVER, NEVER, UNDER PENALTY OF DEATH, SHOULD YOU USE AN APOSTROPHE TO SHOW THE PLURAL OF A NOUN.  Such as here:

Whenever I see mistakes like the ones above, I die a little inside.  Now, go forth and use apostrophes appropriately!  You're welcome.