See also: Feats
You are especially good at using particular weapons.
Prerequisite: Proficient with Chosen Weapon
Effect: Choose a single Exotic Weapon or weapon group, you gain a +1 bonus on all attack rolls you make using the selected Exotic Weapon or weapon group.
Special: You can gain this Feat multiple times. Its effects do not stack. Each time you take the Feat, it applies to a new Exotic Weapon or weapon group.
Additional Weapon Focus Effects Edit
Combined Feat (Weapon Finesse): When you are wielding a single one-handed weapon for which you have Weapon Focus, you can treat that weapon as a Light Weapon.