This eBook was written as the sequel to the eBook titled DC Circuits/ which was written in 2016 by Chad Davis. This eBook covers Alternating Current (AC) circuit theory as well as a brief introduction of electronics. It is broken up into seven modules. Module 1 covers the basic theory of AC signals. Since only DC sources are used in the first eBook/ details of AC signals such as sinusoidal waveforms (or sine waves)/ square waves/ and triangle waves are provided. Module 2/ titled AC Circuits Math Background/ covers the mathematics background needed for solving AC circuit problems. The background material in Modules 1 and 2 are combined in Module 3 to solve circuits with AC sources that include resistors/ inductors/ and capacitors (RLC circuits).