What is means by efficacy of bulb?

The efficacy of a bulb refers to the amount of visible light produced per unit of power consumed, typically measured in lumens per watt (lm/W). It indicates how efficiently a light bulb converts electrical energy into visible light. Higher efficacy values signify that a bulb provides more light for less energy consumed, making it a more energy-efficient choice. This metric is crucial for comparing different types of lighting options, such as LEDs, fluorescents, and incandescent bulbs.