The optimal sleeping light condition is said by some to be total darkness.[8] If a nightlight is used within a sleeping area, it is recommended to choose a dim reddish light to minimize disruptive effects on sleep cycles.[9][3] In addition, nightlights may be useful in locations other than sleeping areas, such as hallways, bathrooms, or kitchens, to allow late night trips to be made without turning on the full light, while preserving a dark sleeping environment.[4]