It was designed originally for the reduction of interferometric data from the Westerbork Synthesis Radio Telescope, but in its history of more than 20 years it has grown to a system capable of handling data from many different instruments (e.g. TAURUS, IRAS etc.).
GIPSY consists of a number of components which can be divided into a number of classes:
M. G. R. Vogelaar and J. P. Terlouw, ``The Evolution of GIPSY, or the Survival of an Image Processing System'', in: Astronomical Data Analysis Software and Systems X, (eds. F. R. Harnden, Jr., F. A. Primini & H. E. Payne), ASP Conf. series Vol. 238, p. 358, 2001. (PostScript, also available in PDF and HTML)