The term for a language’s conventions of spelling, punctuation, and related writing rules is orthography.
Orthography covers more than spelling. Depending on the language, it can include capitalization, word boundaries, hyphenation, emphasis, punctuation, and the relationship between written symbols and speech sounds. English orthography, for example, uses the Latin alphabet but also relies on conventions for silent letters, apostrophes, quotation marks, and compound words.
The word entered English in the 15th century through forms ultimately derived from Greek: orthós, meaning correct, and gráphein, meaning to write. Orthographies often become standardized through schools, printing, dictionaries, governments, newspapers, and other institutions. English has no central language academy, so competing style guides and national traditions help maintain its conventions.
Orthography is not the same as calligraphy, which concerns the visual art or technique of handwriting. Phonology studies a language’s sound system, while etymology investigates word origins. Written systems can also differ in depth: Spanish spelling generally maps sounds more consistently than English spelling, whose irregularities reflect historical sound changes, borrowings, and the influence of Norman and later printing traditions.