(e,e'N) and (e,e'NN) experiments at NIKHEF, Mainz and JLab and open problems in one- and two-nucleon emission

A critical review is presented of recent data on direct one- and two-nucleon emission obtained in electron scattering at NIKHEF, Mainz and JLab. In the case of (e,e${}^{\mathrm{\prime }}$p) reactions attention is focussed on extracting spectroscopic factors, looking at medium effects on the bound nucleon form factors, and investigating nuclear transparency. The possibility of obtaining information on nucleon-nucleon correlations in (e,e${}^{\mathrm{\prime }}$pp) and (e,e${}^{\mathrm{\prime }}$pn) reactions is also discussed.