Hierarchical Data Format (HDF) is a set of file formats (HDF4, HDF5) designed to store and organize large amounts of data. Originally developed at the National Center for Supercomputing Applications, it is supported by The HDF Group, a non-profit corporation whose mission is to ensure continued development of HDF5 technologies and the continued accessibility of data stored in HDF.
In keeping with this goal, the HDF libraries and associated tools are available under a liberal, BSD-like license for general use. HDF is supported by many commercial and non-commercial software platforms, including Java, MATLAB, Scilab, Octave, Mathematica, IDL, Python, R, and Julia. The freely available HDF distribution consists of the library, command-line utilities, test suite source, Java interface, and the Java-based HDF Viewer (HDFView).
The current version, HDF5, differs significantly in design and API from the major legacy version HDF4.
The quest for portable scientific data format, originally dubbed AEHOO (All Encompassing Hierarchical Object Oriented format) began in 1987 by the Graphics Foundations Task Force (GFTF) at the National Center for Supercomputing Applications (NCSA). NSF grants received in 1990 and 1992 were important to the project. Around this time NASA investigated 15 different file formats for use in the Earth Observing System (EOS) project. After a two year review process, HDF was selected as the standard data and information system.
A month of Sundays
And two weeks from Thursday
Halfway across the country this time
Chorus:
Always your face appears in my dreams
And brings me back home tonight
Always your face in my memories
I don't feel alone tonight
Lost on a thru way
And headed the wrong way
can you arms reach me this time
(Chorus)
No one ever warned you
How this life can toss and turn you
When you follow the paths of you dreams
And how these nights feel so long
And these feelings so strong
I would give anything to see you again
Always your face
(Chorus twice)
Always your face
Your precious face