Currently Rennaissance Kingdoms has three kinds of weapons - a staff, for basic fighting/defense, an axe (primarily used for chopping wood), and a sword. Each of the items can affect the way a player can fight and/or defend himself.
The staff(shaft) gives you 1 attack point it costs 10-20 pounds, the axe costs around 170 pounds and give an attack bonus of 2. Lastly the sword gives you 3 attack points and it costs 199-240 pounds.
Note: Staff or sword (also shield) are not useful in the event of robbery for you or for the robber. They are used to calculate points in army events only.