History and Mythology*:
Cancer, the giant crab was sent by Hera to kill Hercules while he was attempting to slay the Hydra as one of his twelve labors. Unfortunately for the crab, Hercules killed it by crushing its shell under his foot. Hera then put the mighty crab in the heavens as a reward for its service even though it was not successful.
Characteristics of the Cancer Sign*:
loyal, resourceful, generous, conservative, loving, kind, sensitive, protective, wise, romantic, sympathetic, sincere
*Note: Information in this product description about the constellation and mythology of Cancer the Crab was drawn from the Wikipedia article.