In Greek mythology, a Gorgon is a creature that is described as having hair made of living, venomous snakes and a horrifying visage that could turn those who beheld them to stone. The term most commonly refers to three sisters: Stheno, Euryale, and Medusa. Traditionally, two of the Gorgons, Stheno and Euryale, were immortal, but their sister Medusa was not and was slain by the demigod and hero Perseus.

Here are some key facts about Gorgons in Greek mythology:

• The Gorgons were female monsters with snakes for hair, who could turn unwitting onlookers to stone in an instant.
• The name "Gorgon" comes from the Greek word "gorgos," meaning "fierce, terrible, and grim".
• The Gorgons were the children of Phorcys, a primordial sea god, and Ceto, a sea goddess.
• In early classical art, the Gorgons were portrayed as winged female creatures with round faces, flat noses, and large projecting teeth.
• Medusa was the only one of the three sisters who was mortal, and Perseus was able to kill her by cutting off her head. From the blood that ran from her neck sprang Chrysaor and Pegasus, her two offspring by Poseidon.
• Carved masks of the Gorgons head were used as a protection against the evil eye.

Overall, the Gorgons were powerful and terrifying creatures in Greek mythology, known for their ability to turn people to stone with just a single look.