The map shows the division of the Norwegian dialects within the main groups.
The Norwegian dialects are commonly divided into 4 main groups, 'Northern Norwegian' (nordnorsk), 'Central Norwegian' (trøndersk), 'Western Norwegian' (vestlandsk), and 'Eastern Norwegian' (østnorsk). Sometimes 'Midland Norwegian' (midlandsmål) and/or 'South Norwegian' (sørlandsk) are considered fifth or sixth groups.
The dialects are generally mutually intelligible, but differ significantly with regard to accent, grammar, syntax, and vocabulary. If not accustomed to a particular dialect, even a native Norwegian speaker may have difficulty understanding it. Dialects can be as local as farm clusters, but many linguists note an ongoing regionalization, diminishing or even elimination of local variations.
Normalized speech, following the written languages Bokmål and Nynorsk or the more conservativeRiksmål and Høgnorsk, is not in common use, except in parts of Finnmark (where the original Sami population learned Norwegian as a second language), in much of østlandet, certain social groups in major urban areas elsewhere (e.g. Trondheim), in national broadcasting, and in courts and official decrees.