what is SPOT colour ?
Spot colours are premade inks that can be used instead of, or in addition to CMYK process colour inks. A spot colour is usually a PMS (Pantone Matching System ® ) colour designated by a number and whether or not the ink is to be printed on specific stock. For example Pantone 123 CVC is used for coated stock and Pantone 281 CVU is used for uncoated stocks. When printing spot colours each colour needs its own plate on the press. Spot colours are mainly used in one to three colour jobs. If you are using four spot colours you may as well make it a CMYK job (unless the colours are absolutely specific to the content). CMYK printing is far cheaper than four spot colours.