JSP Abbrev. for Jackson structured programming. A proprietary brand of structured programming, developed by the British consultant Michael Jackson specifically for use in data processing. He observed that the inputs and outputs of programs could be defined in terms of particular data structures, which are mostly static and easier to define than programs. He then proposed that programs should be constructed by a systematic method based on data structure diagrams.

Two main problems arise. First, it may not be possible to combine the separate data structure diagrams involved in a program because of what are called structure clashes; this is solved by a form of program decomposition called inversion. Second, error handling is not accommodated by the simple method, and gives rise to a technique called backtracking, which is programmed by using assertions and the notation posit/quit/admit.

JSP is used in conjunction with Cobol and PL/I. Translators exist to convert from textual equivalents of Jackson data-structure diagrams into the required target language. It is claimed that the same code will always be produced from a given data specification.

JSP Computing, tradename Jackson structured programming (named after Michael Jackson, computer scientist)
• Japan Socialist Party