Earth Observation System extensions to HDF4

 HDF-EOS4 is a software library designed built on HDF4 to support EOS-specific
 data structures, namely Grid, Point, and Swath. The new data structures
 are constructed from standard HDF data objects, using EOS conventions, through
 the use of a software library [1,4]. A key feature of HDF-EOS files is that
 instrument-independent services, such as subsetting by geolocation, can be
 applied to the files across a wide variety of data products.
 The library is extensible and new data structures can be added.