According to the Oxford English Dictionary, ethics is "The science of morals; the department of study concerned with the principles of human duty."
Philosophers throughout history have been tussling with questions of ethics throughout history, as have each of us in our own lives. Whether we are taught the codes of morality of a particular religion or seek our answers through examination of logic and society, we all confront ethical questions; some of which do not have easy answers.
When facing such problems—in trying to ascertain what is our "human duty" in regard to the relationships in our lives—it is helpful to have a framework within to work. Even if you aren't facing a question of moral ambiguity today, a deeper understanding of how we examine issues of ethics will help you prepare for the questions of tomorrow. The Web sites on our links page will give you a good place to start.