As Graeme McMillan from Time magazine explains, Superman is considered a hero because of the duty he serves to his fellow citizens and the countless lives he saves. Superman also has several superpowers, including X-ray vision, the ability to fly and super-strength, that he employs with great precision as a resource to achieve peace. He fights various threats to mankind and is willing to sacrifice his life in the process.
Superman is actually an alien life-form who fell to Earth from a planet called Krypton. He obtains his powers from the yellow rays of the sun. He didn't have the same capabilities on his home planet, which had a red sun. Superman embodies many of the highest ideals of American society, such as truth, justice and integrity. He is known for his lack of arrogance and genuine concern for helping others. Superman is modest, courteous and humane. He strives to always do the right thing, and his compassion extends even to those who may not otherwise deserve it. Similar to many other superheroes, Superman also has a distinct costume that is easily recognizable, and he fights different archenemies throughout his storyline. He also must remain wary of encountering a radioactive material from his home planet, called kryptonite, which is the only substance that can diminish Superman's powers and leave him defenseless.