韩语 is the standard Mandarin term, especially in mainland China. North Korean usage often appears as 朝鲜语 (Cháoxiānyǔ). Linguistically it's the same language; politically the term used signals which Korea is being referenced.
culture
Korean has been popular among Chinese learners since the Korean Wave (韩流 hanliu) of K-dramas and K-pop took off in the 2000s.
