We give a characterization of ail del Pezzo surfaces of degree 6 over an arbitrary field F. A surface is determined by a pair of separable algebras. From this determination, we derive several consequences, including a computation for the QuillenMoreWe give a characterization of ail del Pezzo surfaces of degree 6 over an arbitrary field F. A surface is determined by a pair of separable algebras. From this determination, we derive several consequences, including a computation for the Quillen K-theory of the surface, an index reduction formula for the function field of the surface, and a criterion for the incompressibility of the surface in terms of the corresponding algebras.