The Infinity Gems (originally referred to as Soul Gems and later as Infinity Stones) are six fictional gems appearing in American comic books published by Marvel Comics, named after and embodying various aspects of existence. The gems can grant whoever wields them various powers in accordance to the aspect of existence they represent, and have the potential of turning the wielder into a god-like being when the main 6 (Mind, Power, Reality, Soul, Space, and Time) are held together. Thus, they are among the most powerful and sought-after items in the Marvel Universe; playing important roles in several storylines, in which they were wielded by characters such as Thanos and Adam Warlock. Some of these stories depict additional Infinity Gems or similar objects. Although, the Infinity Gems altogether give its user nigh-omnipotence, the Gems only function on the universe they belong to and not on alternate realities.
The Gems have appeared in several media adaptations outside of comics, including the Marvel Cinematic Universe film franchise, where they are called Infinity Stones and have their colors altered. These changes were later adapted into the comics.
The first appearance of an Infinity Gem occurred in 1972 in Marvel Premiere #1. It was originally called a "Soul Gem". In 1976, a second "Soul Gem" appeared in a Captain Marvel story which established that there were six Soul Gems, each with different powers. One year later, two more "Soul Gems" were introduced in a Warlock crossover involving Spider-Man. The main six Gems appeared when the death-obsessed villain Thanos attempted to use them to extinguish every star in the universe. In a 1988 storyline in Silver Surfer vol. 3, the Elders of the Universe tried to use 6 of the "Soul Gems" to steal the energy of the world-eating entity Galactus.
In the 1990 limited series The Thanos Quest, Thanos refers to the entire main set as "Infinity Gems" for the first time. In this storyline, he steals most of the Gems for the second time and reveals the Gems to be the last remains of an omnipotent being.