This is a list of free and open source software for geophysical data processing and interpretation. The list is split into broad categories, depending on the intended use of the software and its scope of functions.Notice that 'free and open source' requires that the source code is available. Simple being 'free of charge' is not sufficient—see gratis versus libre. The reader interested in freeware (just free of charge) software is referred to the list of freeware geophysics software.