A footcandle is a unit of measurement for illuminance, which indicates how much light is received on a surface. Specifically, one footcandle is defined as the amount of light produced by one candle at a distance of one foot. This measurement helps in assessing the brightness of a space, making it useful in fields like architecture, photography, and interior design. Footcandles are commonly used to determine appropriate lighting levels for various activities. For example, a well-lit office may require around 50 footcandles, while a dimmer setting, like a restaurant, might only need about 10 to 20 footcandles. Understanding footcandles aids in creating comfortable and functional environments.