The sun gives out white light, and that is the sort of light we’re used to living in much of the time. But old fashioned light bulbs give out a much yellower light. When we’re indoors our eyes adapt to this and we think of this as “white”. If we then see a light source that is genuinely white, it actually looks blue by comparison. We call this a cold light, because we associate blue with cold and red or yellow with warm.
Most low energy bulbs – CFL or LED – are designed to mimic old fashioned bulbs to some extent, and are usually described as “warm white”. This will usually be the preferred option for general household use. Bulbs that are sold as “cool white” are likely to look less attractive but are becoming popular in the kitchens of homes; in the main they are more appropriate for workplace lamps and anywhere where clear vision rather than ambience is the priority.← Do ALL LED Lamps give same colour Light?