How does AC electricity work and what are its fundamental principles?

AC electricity, or alternating current electricity, works by constantly changing direction and magnitude of the electric current. This is achieved through a process called electromagnetic induction, where a changing magnetic field induces an electric current in a conductor. The fundamental principles of AC electricity include the use of Transformers to change voltage levels, the concept of frequency which determines the rate of change in direction of the current, and the ability to transmit electricity over long distances efficiently.