Spoken in both North and South Korea, Korean is the first language of around 77m people.
The Korean language is also spoken in the Chanbai county and Yanbian prefecture in China as well as Sakhalin in Russia and other parts of Central Asia.
Korean is spoken by approximately two million people in China and a similar amount in the US. Korean is also widely spoken in parts of Russia and Japan.
The Korean language is distinct in that it is a language isolate, that is, it has no recognised genealogical relationship with any other language.
Korean has many smaller dialects but the standard form is based on the Seoul dialect and this is spoken in both North and South Korea however the official versions do have slightly different standardised forms.
Although there are many dialects across the two main Korean countries, the language is generally very similar and speakers from the North can easily understand people from the South.
Korean is widely accepted as being one of the most difficult languages to learn for English speakers with the US Defence Language Institute suggesting that the time needed to get to basic proficiency is 63 weeks compared to 25 weeks for French or Italian.
This clearly means that it is important to have experienced native Korean speakers if you need translators or interpreters.