The organization's primary exempt purpose is to ensure the sustainability of hdf technologies and ongoing accessibility of hdf-stored data for the government agencies and organizations that have mission-critical systems relying on hdf. Specifically, the organization's mission is to develop and maintain free, open source computer applications that move and store scientific and complex data among disparate computing systems. There are over 200 different types of computer applications using hdf technologies, and an estimated 1.6 Million users of national aeronautics and space administration (nasa) data alone, in hdf formats.