Finnish ( suomi (help·info), or suomen kieli) is the language spoken by the majority of the population in Finland (92% as of 2006^[update]) and by ethnic Finns outside Finland. It is one of the two official languages of Finland and an official minority language in Sweden. In Sweden, both standard Finnish and Meänkieli, a Finnish dialect, are spoken. The Kven language, a Finnish dialect, is spoken in Northern Norway.

Finnish is the eponymous member of the Finnic language family and is typologically between fusional and agglutinative languages. It modifies and inflects the forms of nouns, adjectives, pronouns, numerals and verbs, depending on their roles in the sentence.

Finnish is a member of the Finnic group of the Finno-Ugric family of languages. The Finnic group also includes Estonian and other minority languages spoken around the Baltic Sea.

Finnish demonstrates an affiliation with the Uralic languages in several respects including:

Several theories exist as to the geographic origin of Finnish and the other Uralic languages, but the most widely held view is that they originated as a Proto-Uralic language somewhere in the boreal forest belt around the Ural Mountains region and/or the bend of the middle Volga. The strong case for Proto-Uralic is supported by common vocabulary with regularities in sound correspondences, as well as by the fact that the Uralic languages have many similarities in structure and grammar.