LEDs and colour | LEDnique

This guide from Lumex gives is a useful quick-reference guide.

Terminology

Suffix	Applies specifically to Lumex products.
Chemistry	The semiconductor doping that produces the characteristic colour.
Number of elements	The number of combined elements in the previous column.
Colour temperature	Applicable to white LEDs.
Peak wavelength	Applicable to monochrome LEDs. Peak wavelength is defined as the single wavelength where the radiometric emission spectrum of the light source reaches its maximum. More simply, it does not represent any perceived emission of the light source by the human eye, but rather by photo-detectors.
Dominant wavelength	Applicable to monochrome LEDs. Dominant wavelength is defined as the single wavelength that is perceived by the human eye. Generally one light source consists of multiple wavelength spectrums from the light source rather than one single wavelength. Our brains turn those multiple spectrums into a single color of light consistent with a single specific wavelength which is what we see when we look at the light. That’s the light source’s Dominant wavelength.
Forward voltage	The minimum and maximum voltages expected.