The Korean language (, see below) is the official and national language of both Koreas: the Democratic People's Republic of Korea (North Korea) and the Republic of Korea (South Korea), with different standardized official forms used in each territory. It is also one of the two official languages in the Yanbian Korean Autonomous Prefecture and Changbai Korean Autonomous County of the People's Republic of China. Approximately 80 million people worldwide speak Korean. 

Historical and modern linguists classify Korean as a language isolate; however, it does have a few extinct relatives, which together with Korean itself and the Jeju language (spoken in the Jeju Province and considered somewhat distinct) form the Koreanic language family. This implies that Korean is not an isolate, but a member of a small family. The idea that Korean belongs to the controversial Altaic language family is discredited in academic research. There is still debate about a relation to Dravidian languages and on whether Korean and Japanese are related to each other. The Korean language is agglutinative in its morphology and SOV in its syntax. 

Modern Korean descends from Middle Korean, which in turn descends from Old Korean, which descends from the language spoken in Prehistoric Korea (labeled Proto-Korean), whose nature is debated, in part because Korean genetic origins are controversial. A relation of Korean (together with its extinct relatives which form the Koreanic family) with Japonic languages has been proposed by linguists such as William George Aston and Samuel Martin. Roy Andrew Miller and others suggested or supported the inclusion of Koreanic and Japonic languages in the purported Altaic family (a macro-family that would comprise Tungusic, Mongolian and Turkic families); the Altaic hypothesis has since been largely rejected by most linguistic specialists.
Was he alone in suggesting that?
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