Korea has one official language (Korean), but there are various regional accents/dialects. The Pusan accent is particularly interesting. Read the following joke to find out why.
One day a Korean lady was standing next to a Foreigner at a bus stop in Pusan, Korea. They were both waiting for the bus. Suddenly the Korean lady sayss, "Watdae*!" and looks at the foreigner.
The foreigner, thinking she was saying, "What day?", answers, "Monday!"
The Korean Lady, thinking that the foreigner was saying, "Muondae**?", answers, "Buseudae***!"
Of course the foreigner still thinks she is speaking English, so he says, "Happy Birthday!"
*Watdae means:
"It has come."
**Muondae means: "What are you
talking about?"
***Buseudae means: "It's the
bus."