A hero is a fictive character who shows bravery, save people, usually has a gentle personality, fight with heroism, love with passion and kills only when necessary.

In Ancient Greece, a hero was a man who had exceptional skills. Heroes were either some gods or some demigods or mythical figure of the mythology. Heroes have always been part of the mythology, like Hercules and his twelve labors, Homer and its crossing or Achilles who fought the Trojan war. Ulysses might be the most famous hero of the mythology. He was just a man but could use his strength as well as his rhetoric to fight the bad ones. He was very cunning and was the one who had the idea of the Trojan Horse.

In fictions, the modern heroes combine the same great qualities and skills, and are often wearing a ridiculous outfit like Superman or Spiderman, who are even said to be superheroes!
However, a modern hero might also be someone who, by his great achievements, is declared to deserve the status of hero. For instance, we call hero some people that fought heroically war, or some people that saved one's life.

For example, the pilot of the Airbus A320 who landed in a panic on the Hudson river, NYC, January, 15, 2009, has soon been called a hero for having saved 155 passengers. This kind of heroes are said to be so because they made an act of bravery for the society or led a fight beneficial to the whole society. For instance, the movie Shindler's list shows very movingly how a German businessman saved the life of a thousand Jews during WW2. This biography features a man we could also call a hero.