Photon and lepton scatterings from the nucleon and nuclei provide snapshots to their structure. A major goal of nuclear physics is to quantitively and comprehensively understand the internal dynamics of the nucleon and nuclei described by Quantum Chromodynamics. Compton scattering is a powerful tool to measure the electromagnetic polarizabilities which are fundamental structure quantities characterizing the response of the nucleon to an external electromagnetic field. At higher energies, deep inelastic scattering of electrons enables the 3D imaging of the nucleon in terms of quarks and gluons. In this talk, I will present different experimental approaches to study the nucleon structure using photon and electron scatterings from nucleon and light nuclei targets.