OK, kiddo, Heracles (pronounced hair-uh-kleez) is a really strong and brave hero from ancient Greek stories. He is also called Hercules in Roman myths. Heracles is mostly famous for completing 12 really tough tasks, which are also called the Labors of Hercules. These tasks were set for him by his enemy King Eurystheus, who thought they were impossible to do.
The first task was to slay a fierce lion with indestructible skin. Heracles did this by choking the lion to death with his bare hands. For another task, he had to clean out a stable that had not been cleaned for years. This task seemed impossible, but Heracles redirected a river to wash out the filth.
Another task was to capture a fleet-footed deer with golden antlers. Heracles pursued the deer for a whole year before finally catching it. He also had to kill a nine-headed hydra, a ferocious monster that grew two heads whenever one was cut off. But Heracles got clever and cauterized the necks of the hydra after cutting off each head so they couldn't grow back.
Heracles completed all the 12 tasks, but he later faced other challenges and adventures, such as battling armies and monsters. He was famous for his immense strength and courage in fighting these battles.
So, Heracles is a legendary hero from ancient Greek and Roman stories who accomplished incredibly difficult tasks with his strength and wit.