What is the difference between principal and principle?

Answer 1

Principal can be a noun or adjective, pertaining to a primary concept:

(noun)

1 - The administrative head of a school (e.g. high school principal)

2 - The amount borrowed in a loan (e.g. paying down a principal)

3 - A participant in an action (e.g. one of the principals in the merger)

(adjective)

4 - Primary, main (e.g. the principal export of the country)

Principle is a noun:

1 - A guiding philosophy or belief, especially a positive one (e.g. a moral principle)

2 - A basic rule governing a study or activity (e.g. a principle of economics)

Answer 2

Principle: it's a kind of rule or the fact of it being.

Example: If someone's rich and lives in a valuable but old building and the government expects the homeowners to pay for the building, the principle of the situation would be the government doesn't pay for the building.

Principal: a person in charge.

Example: the principal at a school.