What is ethical relativism?

Ethical Relativism is operating in a system of situational ethics. Thou shalt not steal, unless you get a chance to steal from a big corporation, the government or someone you don't like. You are faithful to your wife, except on business trips, when everybody cheats, right? Basically, it means being comfortable with shifting your ethics to meet the situation. I try to maintain my ethics in all situations, however though I believe in thou shalt not kill, ants, flies and roaches die if I find them in my house and if you break into my home and come up the stairs, you are a direct threat to my family's safety and I will blow you away with little to no warning. But since I know these are my ethics, family before thief, I do not consider that a case of situational ethics.

Also see "moral relativism".