Colour temperature represents the tint of a light source and is expressed in degrees Kelvin (° K). With today's LED bulbs which offer better colour rendering, we can choose from several shades of white and the general colour of bulbs for our light sources. The different shades fall into 3 main categories: cold white, neutral white and warm white. Warm white is very close to incandescent and halogen bulbs. This type of light evokes the natural light of a sunset. The more orange it is, the more it will have a zen and relaxing effect. This bulb colour is therefore used in living rooms such as the living room and bedrooms.