  We revisit the classifications of classical and quantum galilean particles:
that is, we fully classify homogeneous symplectic manifolds and unitary
irreducible projective representations of the Galilei group. Equivalently,
these are coadjoint orbits and unitary irreducible representations of the
Bargmann group, the universal central extension of the Galilei group. We
provide an action principle in each case, discuss the nonrelativistic limit, as
well as exhibit, whenever possible, the unitary irreducible representations in
terms of fields on Galilei spacetime. Motivated by a forthcoming study of
planons we pay close attention to the mobility of the less familiar massless
Galilei particles.
