Weapons
Weapons are tools of harm. Weapons should be a mixture of simple and unique to be found and experienced.
Damage
Weapons cause a certain amount of harm. This is an abstraction of how capable it is of killing or damaging another thing.
Extra Damage Modifier
Almost all weapons are capable of, with skill, dealing additional damage to other Characters. This is the penalty the weapon has to cause Extra Damage.
Damage Type
Weapons can usually have any of the physical damage types Piercing, Rending, Impact. This will affect what injuries it will cause and what armour will defend against it. Fabrics tend to be strong against Impact, plates against Rending, and weaves against Piercing.
Range
Weapons, unless specified, can only be used to attack things in Reach. Some traits may give a weapon a specific range, however.
Weapon-Traits
Abilities or unique effects a weapon might possess. If you have an idea in mind as a player or game master, try to come up with a unique trait to properly represent a weapon. A non-exhaustive list is provided here.
Quality
Weapons come in various qualities. Higher quality weapons require specific Combat Training to use. For more details on how quality effects a weapon, you can look at Designing Weapons