IMD is a software package for classical molecular dynamics simulations. Several types of interactions are supported, such as central pair potentials, EAM potentials for metals, Stillinger-Weber and Tersoff potentials for covalent systems, and Gay-Berne potentials for liquid crystals. A rich choice of simulation options is available: different integrators for the simulation of the various thermodynamic ensembles, options that allow to shear and deform the sample during the simulation, and many more. There is no restriction on the number of particle types.