Molecular crystallography is a scientific technique used to determine the three-dimensional structure of molecules in solid form. By analyzing the patterns produced when X-rays are directed at a crystal, researchers can identify the arrangement of atoms within the molecule. This method is crucial for understanding the properties and functions of various substances, including proteins and drugs. The process involves growing high-quality crystals of the substance of interest, followed by X-ray diffraction experiments. The resulting data is then processed using mathematical algorithms to create detailed models of the molecular structure. This information is vital in fields like biochemistry and materials science.