Ethics is the branch of philosophy that studies moral principles, values, and rules that guide human behavior, distinguishing right from wrong. It examines how individuals ought to act and what constitutes a good life.

Key principles of ethics include:

1. Autonomy: Respecting individuals’ freedom to make their own choices.
2. Beneficence: Acting to promote the well-being of others.
3. Non-maleficence: Avoiding harm to others.
4. Justice: Ensuring fairness and equality in treatment.
5. Fidelity: Keeping promises and being trustworthy.

These principles often guide ethical decision-making in various contexts, such as medicine, law, and everyday life.