Nowadays, poor solubility, lower bioavailability, and hindered physical, chemical, and biopharmaceutical properties of active pharmaceutical ingredients (APIs) become a very important matter of discussion for pharmaceutical scientists. It is a challenging task for pharmaceutical researchers and industry to develop a suitable formulation with improved physicochemical properties. The process of cocrystallization is long known; however, in the recent times, this approach has gained enormous importance in pharmaceuticals as a relatively new method for enhancement of solubility, bioavailability, stability, thermal properties, permeability, tablet ability, and other related physicochemical properties. Cocrystals are multicomponent systems in which two components, an API and a coformer, were present in stoichiometric ratio and bonded together with non-covalent interactions in the crystal lattice. Cocrystallization offers better optimization of not only physicochemical properties but also therapeutic response and pharmacological properties of APIs. The design of a cocrystallization experiment is based on robustness, hydrogen bonding rules, and potential intermolecular interactions. Various theoretical and experimental approaches increase the chances for selection of a suitable coformer, the most challenging step during the design of cocrystal formation. The present review covers classification of cocrystals, drug selection criteria for cocrystals, chemistry involved in cocrystal formation, methods of preparation, their characterizations, and various applications in pharmaceutical and biomedical fields.