What’s the difference between “warm” lights and “cool” lights?

The only difference is the color temperature of the light. A ‘cool’ light is higher on the kelvin scale and a ‘warm’ light is lower on the kelvin scale.

When we talk about the color temperature of light, we refer to how warm or cool the light appears. This is measured in kelvin (K), with higher kelvin numbers representing cooler, bluer light, and lower kelvin numbers indicating warmer, yellower light. So, when we say a light is 'cool,' it means it has a higher color temperature on the kelvin scale, giving off a bluish-white hue. On the other hand, a 'warm' light has a lower color temperature on the kelvin scale, producing a softer, more yellow-toned glow. By understanding the color temperature of light, you can choose the right lighting for your space to create the desired atmosphere and ambiance.