See also: Character Combat
Striking for Damage with punches, kicks, and headbutts is essentially like Attacking with a Melee Weapon. Unarmed Attacks deal normal Bludgeoning Damage.
A Medium creature normally deals 1d4 points of Bludgeoning Damage (Plus Strength modifier) with a successful Unarmed Attack; A Small creature deals 1d3 points of Bludgeoning Damage (Plus Strength modifier). Certain Talents, Feats, or special abilities may increase the Damage a character deals with their Unarmed Attacks.
Additional Martial Arts and Simple Weapon 
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Reference Book: Star Wars Saga Edition Threats of the Galaxy
For the purpose of Feats and Talents that allow you to select a weapon group for that ability to apply to, Unarmed Attacks are Simple Weapons (Melee). However, Combat Gloves provide a martial artist with a damage advantage that lets them make use of Talents such as Weapon Specialization (Simple Weapons), further increasing their aptitude for Unarmed Attacks. Combat Gloves are considered Simple Weapons (Melee), but attacks with Combat Gloves are still considered to be Unarmed Attacks.
