Clubs are the most basic weapon in Timber & Stone.
To safeguard your settlement against enemies when first starting you should have at least a few people maintain a club in their inventory, if not arming every settler.
However Clubs also have a high mass which can slow down your settlers significantly.
Comparatively the Shortsword has less than half the mass while doing almost double the damage. Because of this it is a good idea to replace clubs as early as possible.