Swedish ( svenska (help·info)) is a North Germanic language, spoken by approximately 10 million people, predominantly in Sweden and parts of Finland, especially along its coast and on the Åland islands. It is largely mutually intelligible with Norwegian and Danish (see Classification). Along with the other North Germanic languages, Swedish is a descendant of Old Norse, the common language of the Germanic peoples living in Scandinavia during the Viking Era. It is currently the largest of the North Germanic languages by numbers of speakers.

Standard Swedish, used by most Swedish people, is the national language that evolved from the Central Swedish dialects in the 19th century and was well established by the beginning of the 20th century. While distinct regional varieties descended from the older rural dialects still exist, the spoken and written language is uniform and standardized. Some dialects differ considerably from the standard language in grammar and vocabulary and are not always mutually intelligible with Standard Swedish. These dialects are confined to rural areas and are spoken primarily by small numbers of people with low social mobility. Though not facing imminent extinction, such dialects have been in decline during the past century, despite the fact that they are well researched and their use is often encouraged by local authorities.