Source : Free On-Line Dictionary of Computing

VPL
     
        1. {visual programming} language.
     
        ["VPL: An Active, Declarative Visual Programming System,
        D. Lau-Kee et al, 1991 IEEE Workshop on Vis Langs, Oct 1991,
        pp. 40-46].
     
        2. A {dataflow} language for interactive image processing.