After Prometheus fooled the gods into accepting the undesirable portions of butchered animals as sacrificial offerings, leaving the nutritious meat for humans, an angered Zeus punished humanity by withholding the gift of fire from them. Distraught, Prometheus stole some fire back, hid it in a fennel stalk, and gifted it to his human creations - allowing them to keep warm, cook food, and generally increase their industriousness.
