Gorgons are very prevalent in Greek mythology and their image adorns many precious items and buildings to protect them.
In Roman mythology, Medusa's story is different and much more tragic. Medusa started life as one of the most beautiful maidens. She was sought after by many men. She was raped by the god Poseidon in the goddess Athena's own temple.
Athena became enraged and so punished the beautiful maiden by making her so incredibly hideous that seeing her face would cause a man to turn to stone. Medusa's beautiful hair was transformed into serpents. Again in this mythology, she is slain by Perseus, who cuts her head off, using his shield to see her reflection and avoiding being turned to stone.