There are two main ways in which the structures of proteins are solved, X-ray crystallography and NMR spectroscopy. Xraycrystallography involves exposing crystallized proteins to beams of X-rays which are diffracted onto & capture by an X-ray film or digital camera. From these diffractions, the exact x, y and z coordinates of the heavy atoms can be determined. NMRspectroscopy, however, measures radio wave absorption by atomic nuclei to determine how much nuclear magnetism is being transferred from one atom to another. Plugging in the values to a computer based program returns several protein structures, which provides an ensemble of different structural configurations for that protein.