A man's car breaks down in the middle of the night...

A man's car breaks down in the middle of the night. He knows the area well and realizes that the quickest way to the nearest service station is through an old graveyard.
He's walking along the headstones when in the distance he hears a faint tapping noise. As he gets deeper into the graveyard, the eerie tapping gets louder and louder. He very anxiously turns a corner and sees the source of the tapping is an old man with a hammer and chisel, hunched over a headstone.
Relief washes over him and he says, "I was beginning to freak out because of that noise. I thought this place might have been haunted. What on earth are you doing here so late at night anyway?"
The old man merely continues chiseling and says "They spelled my name wrong."

This is both a ghost story and a joke. It is supposed to be both funny and scary. The start of the story is fairly normal for a ghost story, but when the old man says "They spelled my name wrong" you are supposed to identify him as some sort of undead person, since you have to assume that the name that they spelled wrong was his name on his own gravestone.

The idea that a ghost would come back from the dead just to correct the spelling of their name on a coffin is funny because usually undead are more interested in doing evil things than in correcting spelling mistakes. That is to say - if he were a zombie, you would expect him to be eating brain instead of correcting spelling mistakes, if her were a ghost he would be haunting somewhere, or if he were a vampire he would be drinking blood, etc.