RGB is an additive, projected light colour system. All colours begin with black “darkness”, to which different colour “lights” are added to produce visible colours. RGB “maxes” at white, which is the equivalent of having all “lights” on at full brightness (red, green, blue). Screens (computer, phone, media player, television, etc are RGB – the pixels have little subpixels that just show red, green or blue.

CMYK is a subtractive, reflected light colour system. All colours start with white “paper”, to which different colour inks are added to absorb (subtract) light that is reflected. In theory, CMY are all you need to create black (applying all 3 colours at 100%). Alas, that usually results in a muddy, brownish black, so the addition of K (black) is added to the printing process. It also makes it easier to print black text (since you don’t have to register 3 separate colours). Most printers print in CMYK.

Please keep in mind, that you can’t display the exact same colors in RGB and CMYK.

IFS Logo CMYK colours:
C100, M70, Y0, K30 (Blue)
C0, M100, Y100, K10 (Red)

IFS Logo RGB colours:
R0, G66, B130 (Blue)
R0, G66,B130 (Red)