The
separation of powers, often imprecisely used interchangeably with the
trias politica principle, is a model for the
governance of a state (or who controls the state). The model was first developed in
ancient Greece. Under this model, the
state is divided into branches, each with separate and independent powers and areas of responsibility so that the powers of one branch are not in conflict with the powers associated with the other branches. The typical division of branches is into a
legislature, an
executive, and a
judiciary. It can be contrasted with the
fusion of powers in a
parliamentary system where the executive and legislature (and sometimes parts of the judiciary) are unified.