A riflescope is an optical device that is installed on the frame of a weapon and makes it easier and faster to aim at target at longer distances. When aiming through conventional fixed sights, the shooter must align the front sight with the rear sight while simultaneously aiming at the target. However, when shooting with a riflescope, it is enough to match the sights with the target, which makes shooting faster, more comfortable and easier. Thanks to the high type of mountings with the so called "sub-sights", it is also possible to aim through fixed sights or even through a riflescope on some models of guns.