Hierarchical Data Format (HDF) is a specification put together by the HDF Group, a consortium of academic and industry organizations (https://support.hdfgroup.org/HDF5/). In HDF5 files, data is organized into groups and datasets. A group is a collection of groups or datasets. A dataset is a multidimensional homogeneous array.
In Python, PyTables and h5py are two major libraries for handling HDF5 files. Both these libraries require HDF5 to be installed. For the parallel version of HDF5, a version of MPI is also required to be installed. Installation of HDF5 and MPI is beyond the scope of this book. Installation instructions for parallel HDF5 can be found at the following link: https://support.hdfgroup.org/ftp/HDF5/current/src/unpacked/release_docs/INSTALL_parallel.