Crossbow

The Crossbow is a type of mechanized bow that uses a pulley to and single-shot feeding mechanism to fire bolts, which are arrows with a shorter shaft, allowing them to fly farther due to reduced weight. It is named for it's cross-shaped design. It operates on the same principle as the traditional bow and arrow in that a tough bowstring is pulled back to build up momentum with a projectile in front of it to be the recipient of said momentum, and suddenly released to launch the projectile.

The difference is that a bow and arrow needs to be pulled back the moment before it starts shooting, which can cost the bowman the initiative of a first strike. Crossbows, however, had a pull and lock mechanism that passively locks the bowstring in a readied state and only requires the bowman to operate the trigger, the moment he needs to let a bolt fly. Said mechanisms typically vary, some crossbows used a winding pulley, some used levels, while some used a crank-operated pulley.

Use in warfare

The biggest advantage of crossbows over regular bows is that much like firearms, because they're fired using a mechanism instead of purely human strength, fatigue is no longer largely a factor for bowmen since crossbows fire at a usually constant force. Additionally, the crossbow could generate more force than most humans thanks to the pulley system, thus, arrows flew faster and harder, to a point where even the plate armor of knights were easily penetrate by them. And additionally, much like firearms, it was easier to train peasant militia with the use of crossbows than bows since the weapon's operation is much simpler.

Of course, the main drawback with crossbows is that they require more time, labor and resources to produce, along with skilled craftsmen to craft the bow's design and feeding mechanism, compared to bows which are vastly less laborious and specialized to produce.