Crossbows have been used for warfare for over 2,500 years, developing across multiple cultures from China to Europe. They provided an advantage over traditional bows by allowing a greater torque to be built up, increasing the velocity and penetrating power of projectiles. While eventually replaced by gunpowder weapons, crossbows remained effective until the 1500s and some are still used today for hunting or historical reenactments. They function by storing elastic potential energy in the drawn bowstring and releasing kinetic energy via a trigger mechanism.