An orthography is a set of conventions for writing a language, including norms of spelling, hyphenation, capitalization, word boundaries, emphasis, and punctuation.

Most transnational languages in the modern period have a writing system, and most of these systems have undergone substantial standardization, thus exhibiting less dialect variation than the spoken language. These processes can fossilize pronunciation patterns that are no longer routinely observed in speech (e.g., "would" and "should"); they can also reflect deliberate efforts to introduce variability for the sake of national identity, as seen in Noah Webster's efforts to introduce easily noticeable differences between American and British spelling (e.g., "honor" and "honour").

Some nations (e.g. France and Spain) have established language academies in an attempt to regulate orthography officially. For most languages (including English), no such authority exists, and a sense of "correct" orthography develops through encounters with print in schooling, workplace, and informal contexts. Some organizations, such as newspapers of record and academic journals, choose greater orthographic homogeneity by enforcing a particular style guide.