  We consider the Galilean group of transformations that preserve spatial
distances and absolute time intervals between events in spacetime. The special
Galilean group SGal(3) is a 10-dimensional Lie group; we examine the structure
of the group and its Lie algebra and discuss the representation of uncertainty
on the group manifold. Along the way, we mention several other groups,
including the special orthogonal group, the special Euclidean group, and the
group of extended poses, all of which are proper subgroups of the Galilean
group. We describe the role of time in Galilean relativity and touch on the
relationship between temporal and spatial uncertainty.
