Definition Section - PDS) and one optional (Grid Description Section - GDS). The PDS describes who created the data (the research / operation center), the involved numerical model / process (can be NWP or GCM), the data that is actually stored (such as wind, temperature, ozone concentration etc.), units of the data (meters, pressure etc.), vertical system of the data (constant height, constant pressure, constant potential temperature), and the time stamp. If a description of the spatial organization of the data is needed, the GDS must be included as well. This information includes spectral (harmonics of divergence and vorticity) vs gridded data (Gaussian, X-Y grid), horizontal resolution, and the location of the origin. Software Applications A number of application software packages have been written which make use of GRIB files. These range from command line utilities to graphical visualisation packages. ATMOGRAPH ModelVis Commercial numerical weather model data visualization software capable of decoding and displaying both GRIB 1 and GRIB 2 data formats ArcGIS Market leading GIS software Expedition – Expedition is the Sailing navigation and weather application. Grib display and download from many sources is free. cfGrib is a State-Of-the-Art grib parsing tool for python based on ecCodes from ECMWF. WGRIB Command line based program to manipulate, inventory and decode GRIB1 files GrADS, free command line based desktop application that directly handles GRIB1 and GRIB2 files Picogrib GRIB 1 C-language (FORTRAN callable) free decoding package compatible to some extent with ECMWF GRIBEX routine NCEP codes free software (C and FORTRAN library) for decoding and encoding data in GRIB 1 format NCEP codes free software (C and FORTRAN library) for decoding and encoding data in GRIB 2 format (some template only) JGrib - Jgrib is a free library for reading GRIB files in Java. Meteosatlib - Meteosatlib is a free software C++ library and set of tools to convert satellite images between various formats; it can read and write GRIB data, and its GRIB encoding/decoding library can be used standalone. Mathematica, a general mathematical, statistical, and presentation application directly handles GRIB files and can map them with many projections The NCAR Command Language can be used to read, analyze and visualize GRIB data, as well convert it to other gridded data formats. PyNIO is a Python programming language module that allows read and/or write access to a variety of data formats using an interface modelled on netCDF. degrib (AKA NDFD GRIB2