Bows are one of six weapon classes in Titan Quest. They are two-handed weapons used for ranged combat. All bows have a very slow Attack Speed and do 25% Pierce Damage, however some Epic and Legendary bows, like Telliam's Will do 50% Pierce Damage. Pierce damage ignores the target's armor, instead it gets reduced by their pierce resistance.
Bows are the only items in Titan Quest that can be enhanced with the Artemis' Bowstring relic, which adds pierce damage and attack speed to the bow.
The Hunting Mastery has many skills focused on the use of bows, several of which are dedicated to enhance ranged combat using the bow.