In project zomboid, there are a variety of tools. Some of these tools are used in constructions, others for modifying weapons.
These tools are used to modify bases and to make them more zombie-resistant.
Planks: To make barricades and to craft various pieces
Nails: To put the barricades and to craft various wall pieces, and to modify weapons.
Hammer: To craft items and to make barricades and to modify weapons
Sledge: To demolish walls
These tools have other purposes
Can Opener: To open cans of canned food to eat them.
Saw: To modify weapons and to change logs into planks.