Anger, also known as fury, anger, wrath and temper is the most basic definition of violence, provoked violence. The second type of violence, the external one, in the Iliad is that of the Gods, the immortals, the true "rulers" of the world. And finally there is Achilles, the third type of violence, the internal violence, in the Iliad, is almost worse than the first two types of violence. All of this is in the first book of the Iliad, I think it would be a safe statement to say that there are more than just three types of violence in the rest of the world.