Massively Parallel Monte Carlo (MPMC) is an Monte Carlo method package primarily designed to simulate liquids, molecular interfaces, and functionalized nanoscale materials. It was developed originally by Jon Belof and is now maintained by a group of researchers in the Department of Chemistry and SMMARTT Materials Research Center at the University of South Florida. MPMC has been applied to the scientific research challenges of nanomaterials for clean energy, carbon sequestration, and molecular detection. Developed to run efficiently on the most powerful supercomputing platforms, MPMC can scale to extremely large numbers of CPUs or GPUs (with support provided for NVidia's CUDA architecture). Since 2012, MPMC has been released as an open-source software project under the GNU General Public License (GPL) version 3, and the repository is hosted on GitHub.