PMS colours are patented and standardized coloured inks. PMS is used for offset printing and is ideal for stationery. PMS is also used for a spot colour on flyers in addition to CMYK printing.
CMYK is a process where tiny dots of Cyan, Magenta, Yellow and Black inks are mixed to make different colours. Used mostly in digital printing. Ideal for full-colour flyers, posters, banners and other signage.
RGB is a process where Red, Green and Blue are combined to create different colours. Used mostly for online applications and Email Signature designs..
HEX colour is a six-digit combination of letters and numbers that represents an RGB colour. It is mainly used in Website Design