Fourspace

Fourspace, sometimes written four-space or four spaces, is a term used to describe a convention in typography and computing that refers to indentation or spacing equal to four space characters. The term is not a formal standard but is used to describe a fixed-width indentation style across editors and languages.

In programming, four-space indentation is widely associated with readability and consistency. It is the conventional indentation width in Python, as codified by PEP 8, which prescribes using four spaces per indentation level and discourages the use of tab characters. Many other languages and style guides also adopt four spaces or allow configuration to convert tabs into four spaces. Developers sometimes customize their editors to maintain this width automatically to avoid mixing tabs and spaces.

In plain-text and markup contexts, four-space indentation has historically signified a preformatted block. In early Markdown and other markup languages, lines indented by four spaces were treated as code blocks; in modern Markdown, fenced code blocks are more common, but four-space indentation remains a recognizable alternative in older documents and emails.

In typography, four spaces can indicate a paragraph indent in certain traditional typesetting or proofreading conventions, though modern typography often uses a smaller or variable indentation or a hanging indent for lists.

Overall, fourspace is a descriptive term rather than a fixed standard, used to discuss indentation and spacing practices in both coding and typographic contexts.