Power ratio is a term commonly used in the field of engineering and physics that refers to the ratio of output power to input power of a system. This ratio can be expressed in different ways, including Watt ratio, energy ratio, and voltage ratio. Other synonyms for power ratio include power gain, amplification factor, attenuation ratio, and signal-to-noise ratio. In radio communication, power ratio can be expressed as dBm or dBW, which stands for decibels relative to milliwatt or watts. Power ratio is an important concept in many applications, including audio systems, electronics, renewable energy, and more.