  We find that in order to completely describe the spin transport, apart from
spin current (or linear spin current), one has to introduce the angular spin
current. The two spin currents respectively describe the translational and
rotational motion of a spin. The definitions of these spin current densities
are given and their physical properties are discussed. Both spin current
densities appear naturally in the spin continuity equation. Moreover we predict
that the angular spin current can also induce an electric field $\vec{E}$, and
in particular $\vec{E}$ scales as $1/r^2$ at large distance $r$, whereas the
$\vec{E}$ field generated from the linear spin current goes as $1/r^3$.
