Alternating current is a term commonly used in electrical engineering and refers to the type of electric current that changes direction periodically. This type of current is the most common form of energy that is used in homes and businesses around the world. However, there are several synonyms for alternating current that can be used interchangeably. Some of these synonyms include AC, cyclic current, sinusoidal current, and periodically reversing current. They all refer to the same type of electric current characterized by the flow of electrons that reverse direction periodically, resulting in a sinusoidal wave pattern. Regardless of the preferred term used, the importance of alternating current is undeniable in the modern world.