I have heard of a lemon law? Does this law really exist? What all does it mean and who does it apply to?

I live in NC and I recently heard about something called a lemon law. Is this just for my state, or do all or most states have this law?

It is a state by state situation, like most laws in the United States. I don't know whether NC has it, but some states certainly do, though the details will vary by the state.

Lemon laws involve a consumer's right to a refund for a motor vehicle that, despite repreated attempts to fix it, continues to be defective in a significant way.

Here is a website describing laws such laws generally, and which has a link to take you to the laws of the individual states:

http://www.autopedia.com/html/HotLinks_LemonState.html

You will see the basics of North Carolina's law there.

This site specifically has NC's lemon laws:

http://www.autosafety.org/article.php?did=241&scid=66

This refers to merchandise. Buying something (say a car) and then the mechanics don't work. That would be "buying a lemon".. Carfax has a service to ensure you don't receive a "lemon". Most states have this law.

Yes, there is a lemon law and it is different in each state. Some states if a vehicle has to get the same thing fixed more than 6 times it would be considered a lemon, hence "lemon law". Be sure to look into the details of your state if you ever have an issue.