Hercules is the Roman name, who was the son of Zeus (Jupiter) and the mortal Alcmene.
He is famous for his strength and for his numerous adventures. His jealous stepmother, Juno, tried to murder the infant Hercules. She sent two huge snakes to strangle the little baby. But Hercules just sat up and grabbed those snakes and strangled them. He was a great hero, and very strong.
When Hercules grew up, he was really the strongest man in the world. He married a woman named Megara and they had two children, whom he loved very much. But Hera was angry at Hercules. Hera struck him with a fit of madness during which he killed his wife and children.
When Hercules come to his senses, he was horrified by what he had done. He needed to find some way for the gods to forgive him for this terrible crime. He went to Delphi and asked Apollo what to do. Apollo said the gods would forgive Hercules if he did twelve hard jobs for Eurystheus, the king of Argos.
These tasks are known as the twelve labours of Hercules.
It took Hercules twelve years to complete those twelve tasks and became a free man.
Hercules had many other adventures during his lifetime. He killed other beasts and monsters, in numerous battles against his enemies.
Later, Hercules married Deianeira, a princess whose hand he had won by fighting the river god Achelous.