HDF is an acronym for Hierarchical Data Format - a data file format for storing scientific data, allowing one to organize data into datasets as multidimensional arrays, and groups of objects.HDF homepage at: https://www.hdfgroup.org/products/ tekbasseUser guide for HDF4: https://www.hdfgroup.org/release4/doc/UsrGuide_html/UG_Utils.html(previous: See http://freshmeat.net/projects/hdf/ for links to the HDF home page.)