There have been numerous types of slavery practiced throughout history, including full ownership and indentured servitude. In the ancient world, slaves were taken during wartime by the victors, and were often physically marked as slaves. For example, publicly-owned slaves in ancient Athens were tattooed with the image of an owl on their faces, as the owl was the symbol of Athena, patron goddess of Athens. Unlike in the United States, slaves in the ancient world were allowed to save money and eventually buy their freedom. In indentured servitude, servants/slaves had to work long enough to pay off a debt (such as the price of one’s passage to the American colonies).