Structure functions at low Q2: higher twists and target mass effects

We review the physics of structure functions at low Q2, focusing on the phenomenon of quark-hadron duality and the resonance–scaling transition, both phenomenologically and in the context of quark models. We also present a new implementation of target mass corrections to nucleon structure functions which, unlike existing treatments, has the correct kinematic threshold behavior at finite Q2 in the x→1 limit.