OpenFOAM is an open-source software package for solving and analysing continuum mechanics problems, most prominently for computational fluid dynamics (CFD). OpenFOAM is written in C++ and is mainly developed by CFDDirect on behalf of the OpenFOAM Foundation. The source code is published under GNU GPL v3 license. OpenFOAM is developed for flexibility, extensibility, robustness and maintainability, key features that allow a broad range of applications and customization for research.