Typographical syntax

Typographical syntax, also known as orthotypography, is the field of microtypography that defines the meaning and rightful usage of typographical signs (notably punctuation marks) and various elements of layout such as flushing or indentation.

Orthotypographic rules, when they are not imposed by grammar, vary broadly from language to language, and even from publisher to publisher. As such, they are more often defined as "conventions".

While some of those conventions are justified by ease of understanding criteria – for instance specifying that low punctuation (commas, full stops, and ellipsis) must be in the same typeface, weight, and style as the preceding text –, many are probably arbitrary.

A good example of this is the rules dealing with quotation marks: which ones to use and how to nest them, how much whitespace to leave on both sides and where to integrate them with other punctuation marks.

Each major publisher maintains a (different) list of orthotypographic rules they apply as part of their house style.