Skill Gems are special items in the game Path of Exile that allow players to customize their character's abilities. Each gem represents a specific skill, such as casting spells or performing attacks, and can be socketed into equipment to activate these skills. Players can find or purchase these gems throughout the game, and they come in different colors, which correspond to the attributes required to use them. As players progress, they can level up their Skill Gems by using them in combat, enhancing their power and effectiveness. Additionally, players can combine Skill Gems with Support Gems to modify their skills further, adding effects like increased damage or area of effect. This system encourages experimentation and allows for diverse character builds.