Language language
The Korean language is shared between both North and South Korea and is part of the Altaic language family. There are various dialects but the language is generally understood everywhere. 65 million people speak the Language, with 45 million speaking it in South Korea. The language is considered one of the best and most well planned languages in history. Hangul is the Korean name of the language. The alphabet was created by King Sejong in 1446. The alphabet is extremely easy to learn, which gives Korea one of the highest literacy rates in the World.
I once heard this childrens story about the language.
Story of the Language
You can also read up - in more detail, about the history of the language below.
Hangul on Wikipedia
Many Koreans also study English. It is taught from very early on in school. Many signs will be in both Korean and English. If you visit Korea, do not be worried if you do not know much of the language. You will learn what you need quickly and many Koreans will be able to speak some English.