CMYK vs RGB

CMYK- Cyan, Magenta, Yellow and Key (Black.)

RGB- Red, Green and Blue

The RGB colour mode uses red, green and blue and is able to combine these to create most other colours using an 'additive' method. This mode is usually used for computer monitors, LED televisions and digital cameras. Programs like Photoshop also use RGB as it can achieve a multitude of colour variations.

CMYK on the other hand is becoming more of an uncommon mode, however it is mostly used for printing. It uses cyan, magenta, yellow and black in a layering method, with the exception that offset printers can use a “spot” colour which can be used to make a specific colour swatch, usually a Pantone colour. If you were to add all the CMYK colours together it would become darker, whereas with the RGB mode in varying amounts you'll end up with white.