In 2014, developers released the first weapon case with community-made finishes, the Winter Offensive Weapon Case. Most up-voted skins would get a chance to appear in future CS:GO updates. With the Arms Deal update, Valve also announced that players will be able to upload their own weapon finishes and custom knife models through the CS:GO Workshop. Free cosmetics are getting dropped upon completing matches in official game modes. With the new update, players got a chance to receive a free case after finishing a match on a VAC-secured server.
The Arms Deal update blessed the players with the first CS:GO skins that you could get by opening weapon skin cases with case-specific keys. The history of CS:GO weapon skins starts in 2013, a year after Counter-Strike: Global Offensive was officially released.