Prometheus (meaning "Forethought") was one of the masterminds of the battle between the Titans and the Olympian Gods led by Zeus to gain control of the heavens, a struggle which was said to have lasted ten years. Prometheus switched sides and supported the victorious Olympians when the Titans would not follow his advice to use trickery in the battle.
Don't exhaust all your gifts.
To reward Prometheus and Epimetheus for their contributions to the Godly struggle during the war, Zeus allowed Prometheus and his brother, Epimetheus to create life on Earth. Prometheus made the first humans out of clay; Epimetheus was to spread gifts to all the creatures of the Earth so that they may prosper.
You, have wings, to you, I give feathers. To all, I give gifts so that you may thrive.
Once Epimetheus arrived at the humans to give them their gifts, he had exhausted all of his endowments, and had nothing left to give.
Angered with the weakness of his creation, and feeling sorry for them, Prometheus invaded the workshop of Hephastus and Athena on Mount Olympus, and stole fire, hiding it in a hollow fennel stalk.
They'll never know.
Prometheus gave the valuable gift to man, hoping that it would help him in his struggle. He taught man how to use the gift, and thus began the art of metalworking and cooking.
HOW DARE HE?!?
Outraged by Prometheus' theft of fire, Zeus decided to punish Prometheus.