Specificaly to The Elder Scrolls V: Skyrim:
Crossbows are useful in several ways. They don't affect walking speed, shoot faster arrows and have a higher base damage, all useful when hunting vampires. They can also be used in combination with element infused arrows that inflict frost, flame or lightning damage on the target. You don't have to wait for the bow to be drawn before shooting and thus can be ready to fire before entering battle. You have a higher chance to stagger the enemy across the board, both when they are hit by an arrow and when you bash them.
"now days" crossbows are used mainly for sport although the crossbow is still classed as a dangerous weapon
crossbow
Human + Weapon = Sword, Crossbow
Weapon Masters - 2007 Chinese Repeating Crossbow was released on: USA: 20 October 2008
They were used in ancient times as the first weapon of choice because they could penetrate several layers of armour
Because it was a weapon that could pierce the armor of knights so it made it possible for anyone to kill a knight it was too powerful of a weapon
Because they are effective, accurate weapon.
A crossbow.
A crossbow is a composite weapon, meaning it is made out of many parts. A regular bow, however, can be a single stick with a length of string, so the crossbow is harder.
This is because the 'Cross bow' is actually a Bowcaster, a weapon used by Wookiees that fires explosive bolts encased in energy. It is a very heavy weapon that requires the strength of a Wookiee to operate.
long bow
You can't its just a weapon in the beginning video of the game.