Color temperature refers to the type of white light that is emitted. “Warm” white lights emit a softer, yellower light, while “cool” white lights give off a bluer, more intense light. Color temperature is measured in Kelvins (K), and typically ranges from 2000K-6500K. The lower the Kelvins, the warmer the light that is emitted.
Typically, a warm white bulb for the home would be one with a color temperature between 2700K-3000K, while a cool white light would be anywhere above 4000K. “Daylight” lights are the coolest available, with a color temperature around 6500K, and are supposed to mimic the type of light the sun gives off during the day. These lights would give off a very harsh, blue light if used in the home or office.