Here's a breakdown:

* Concept: A principle can be the fundamental idea or truth behind a concept. For example, the principle of democracy is the idea that power resides with the people.

* Rule: A principle can act as a guiding rule or law that governs behavior or actions. For example, the principle of "do unto others as you would have them do unto you" is a moral guideline.

* Standard: A principle can set a standard or benchmark for something. For example, the principle of sustainability sets a standard for environmental responsibility.

In essence, a principle is a fundamental truth or guideline that helps us understand, interpret, and navigate the world around us.