Two-Weapon Fighting [General]
You can fight with a weapon in each hand. You can make one extra attack each round with the second weapon.
Prerequisite: Dex 15.
Benefit: Your penalties on attack rolls for fighting with two weapons are reduced. The penalty for your primary hand lessens by 2 and the one for your off hand lessens by 6.
Normal: If you wield a second weapon in your off hand, you can get one extra attack per round with that weapon. When fighting in this way you suffer a -6 penalty with your regular attack or attacks with your primary hand and a -10 penalty to the attack with your off hand. If your off-hand weapon is light the penalties are reduced by 2 each. (An unarmed strike is always considered light.)
Special: A 2nd-level ranger who has chosen the two-weapon combat style is treated as having Two-Weapon Fighting, even if he does not have the prerequisite for it, but only when he is wearing light or no armor.
A fighter may select Two-Weapon Fighting as one of his fighter bonus feats.
Source: SRD 3.5 Feats