Suppose that "X" is a Noetherian scheme. An abelian étale sheaf "F" on "X" is called finite locally constant if it is a representable functor which can be represented by an étale cover of "X". It is called constructible if "X" can be covered by a finite family of subschemes on each of which the restriction of "F" is finite locally constant. It is called torsion if "F"("U") is a torsion group for all étale covers "U" of "X". Finite locally constant sheaves are constructible, and constructible sheaves are torsion. Every torsion sheaf is a filtered inductive limit of constructible sheaves.