This note aims at clarifying some mathematical aspects of what is known in Physics as \emph{ Picture Changing Operator} (PCO). In particular, we want to show that PCOs are chain maps between the complex of differential forms (or superforms) and the complex of integral forms on a given supermanifold. We comment on the construction of (super)symmetric PCOs in terms of chain homotopies and we provide some physically relevant examples of applications.
Categories: math-ph hep-th math.AG math.DG math.MP