HDF - Hierarchical Data Format File
This is a standard file format to store scientific data which is used in environmental science, non-destructive testing, aerospace applications and even neutron scattering. Utilities that use these files can view, analyze, manipulate, visualize and convert data in HDF files. HDF4 and HDF5 are the two most commonly used versions and each version includes libraries which contains functions to manipulate and analyze the data in HDF files. The HDF Group keeps a list of software packages which can read and utilize HDF files and one popular open source package is GDAL which stands for The Geospatial Data Abstraction Library.