Hermes2D is a C++ library for rapid development of adaptive hp-FEM / hp-DG solvers. Novel hp-adaptivity algorithms are designed to solve a large variety of problems ranging from ODE and stationary linear PDE to complex time-dependent nonlinear multiphysics PDE systems. The code is distributed under the GNU General Public License (Hermes2D and Hermes3D) and BSD License (Hermes1D). The hp-FEM group at the University of Nevada, Reno and University of West Bohemia, Pilsen is concerned with the development, implementation, and dissemination of modern computational methods for engineering and scientific problems described by partial differential equations (PDE). Our work is freely available through several open source projects.