The SKS is a semi-automatic carbine designed by Sergei Gavrilovich Simonov in 1943. Chambered for 7.62x39mm round, the SKS was extremely reliable and simple in design. It had two distinguishing characteristics: one is a permanently attached folding bayonet, the second being a non-detachable magazine. Incapable of fully automatic fire and limited by its ten round magazine capacity, it was later replaced by the AK-47 that was introduced in the 1950s.
Gas-operated from a tilting bolt, the SKS represented a step towards the development of what we now recognize as assault rifles. It was shorter and less powerful than the semi-automatic rifles that preceded it which resulted in a higher muzzle velocity than the firearms that replaced it. Overall, the SKS remains popular on the civilian market as a hunting and marksmanship firearm in various countries, including the United States and Canada.