A DataFormat is a formal language for the representation of information. Unlike ProgrammingLanguages, DataFormats don't specify computations. 

Examples of data formats are BibTeX, XML, HTML.

LaTeX is a good example of the vague boundary between DataFormats and ProgrammingLanguages; although it is intended (and perceived) as a data format for the specification of documents, it is in fact a TuringComplete programming language. This makes it a very powerful document preparation system, but makes it also very difficult to use LaTeX documents for other purposes than translation to PostScript. (The HeVeA translator achieves a fairly good translation to HTML though.)

SDF is another example for which it is hard to decide whether it is a data format or a programming language. An SDF specification defines the syntax of language completely declaratively. This definition can be used to generate a parser, so one could argue that an SDF definition specifies computations. 

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CategoryLanguage | Contributors: Main.EelcoVisser