Since the pioneering experiments of Hofstadter and others in the 1950’s the measurement of nucleon electromagnetic form factors has been one of the primary sources of information about the charge and current distributions within nucleons. In addition to nucleon elastic scattering, form factors play a major role for other processes. A number of experiments at Jefferson lab have been devoted to measuring elastic and transition form factors including large angle Compton scattering, meson electroproduction, and excited nucleon resonance electroproduction. This talk will review some of these measurements and their interpretation in terms of generalized parton distributions. Information which they provide about the electromagnetic charge and current distributions in the nucleons will be discussed.
