A standard variety is developed from a group of related varieties. This may be done by elevating a single dialect, such as the local variety of a center of government or culture. Alternatively, a new variety may be defined as a selection of features from existing varieties. A fixed orthography is typically created for writing the variety. It may be codified in normative dictionaries and grammars, or by an agreed collection of exemplary texts. Whether these dictionaries and grammars are created by private individuals (like Webster's Dictionary) or by state institutions, they become standard if they are treated as authorities for "correcting" language. A fixed written form and subsequent codification make the standard idiom more stable than purely spoken varieties, and provide a base for further development or ausbau. This variety becomes the norm for writing, is used in broadcasting and for official purposes, and is the form taught to non-native learners.
Through this process, the standard variety acquires prestige and a greater functional importance than local varieties. Those varieties are said to be dependent on, or heteronomous with respect to, the standard idiom, because speakers read and write the standard, refer to it as an authority is such matters as specialist vocabulary, and any standardizing changes in their speech are towards that standard. In some cases, such as Standard English, this process may take place over an extended period without government intervention. In others it may be deliberately directed by official institutions, such as the Académie française or Real Academia Española, and can proceed much more quickly.
Language standardization is often linked to the formation, or attempted formation, of nation states, as language is seen as the vehicle of a shared culture. Different national standards derived from a dialect continuum may become treated as different languages, even if they are mutually intelligible. The Scandinavian languages, Danish, Norwegian and Swedish, are often cited as examples.
In other cases governments or neighbouring populations may seek to deny a standard independent status.
In response, developers of a standard may base it on more divergent varieties. Thus after Norway became independent at the start of the 20th century, the Bokmål standard based on the speech of Oslo was felt to be too similar to Danish by Ivar Aasen, who developed a rival Nynorsk standard based on western dialects. Similarly, when a standard was developed in the Yugoslav republic of Macedonia from local varieties within a continuum with Serbia to the north and Bulgaria to the east, it was deliberately based on vernaculars from the west of the republic that were most different from standard Bulgarian. Now known as Macedonian, it is the national standard of the independent Republic of North Macedonia, but still viewed by Bulgarians as a dialect of Bulgarian.