Nucleon electromagnetic form factors

Nucleon electromagnetic form factors are fundamental quantities related to the charge and magnetization distributions inside the nucleon. Understanding the nucleon electromagnetic structure in terms of the underlying quark and gluon degrees of freedom of quantum chromodynamics is a challenging and urgent task. The nucleon electromagnetic form factors have been studied in the past extensively in unpolarized electron scattering experiments. With the development in polarized beam, recoil polarimetry, and polarized target technologies, polarization experiments have provided more precise data on these quantities. At the same time, significant theoretical progress in areas ranging from effective field theories to lattice QCD calculations, has been made in describing these data. In this article, we review recent experimental and theoretical progress on this subject. We also provide the future outlook on this topic.