Electron diffraction is a technique used to study the structure of materials at the atomic level. It involves directing a beam of electrons at a sample, which causes the electrons to scatter. The resulting pattern of scattered electrons provides information about the arrangement of atoms in the material. This method is particularly useful in materials science and solid-state physics because it can reveal details about crystal structures and defects. By analyzing the diffraction patterns, scientists can determine the spacing between atoms and the overall symmetry of the material, helping to advance our understanding of various substances.