Alternating current (AC) is a type of electrical current that periodically reverses direction. Unlike direct current (DC), which flows in a single direction, AC changes its flow back and forth, typically in a sinusoidal waveform. This characteristic makes AC suitable for powering homes and businesses, as it can be easily transformed to different voltages. AC is generated by power plants and transmitted over long distances through power lines. The ability to change voltage levels allows for efficient transmission, reducing energy loss. Most household appliances, such as refrigerators and televisions, operate on AC, making it a fundamental part of modern electrical systems.