what does watt measure

A watt is a unit of measurement for power, which is the rate at which energy flows. Specifically, one watt is equivalent to electricity flowing at a rate of one joule per second in the metric system. The watt is named after James Watt, the inventor of the steam engine. Power consumption of small devices is typically measured in watts, while power consumption of larger devices is measured in kilowatts (kW), where one kW is equal to 1,000 watts. Its important to note that when buying light bulbs, wattage does not equal brightness, as brightness is measured in lumens.