Solids are characterized by short intermolecular distance and strong intermolecular forces. Their constituent particles which can be atoms, molecules or ions have fixed positions unlike liquids or gases and can only oscillate about their mean positions. This happens because of the short inter- and intramolecular bond lengths and strong intermolecular forces. It takes a large amount of energy to break these forces and to make solids compressible. Hence, solids are incompressible.