In computing a data-structured language is a programming language in which the data structure is a main organizing principle, representation, model, for data and logic (code) alike, in which both are stored and operated upon, i.e., program data and logic are structured and operated on in the same way, by the same representation. These are generally well suited to reflection and introspection, and are in some ways more consistent than many other languages. This makes them easier to learn, and to program in for those problems which naturally fit the language's data structure. Where this occurs, programming may become trivial. For those problems which do not naturally fit a language's data structure, programming may be no easier or even harder than in other languages.

Structured data has the advantage of being easily entered, stored, queried and analyzed. At one time, because of the high cost and performance limitations of storage, memory and processing, relational databases and spreadsheets using structured data were the only way to effectively manage data. Anything that couldn't fit into a tightly organized structure would have to be stored on paper in a filing cabinet.