Physical Damage: Humans vs Orcs

I am finally at a point where I am pretty comfortable beating the easier of the Hard dungeons. I am at the point where I am steadily beating hard dungeon quests to unlock Vicious dungeons and more quest items. At this stage, I feel a need to better understand the basics of the Human vs Orcs. I mostly choose Orcs for no reason. Can someone please help me better understand this.