While monitors use RGB (Red Green Blue) to preview full-colour images (so type of colour is not an issue), traditional printing uses CMYK (Cyan, Magenta, Yellow, Black) also known as Four Colour Process printing (or simply Four Colour). In this method of printing, the design is set up so that it uses percentages of the 4 base inks. These percentages are created using varying sizes and densities of dots - most noticeable in the low resolution printing of most newspapers (see below).



When these varying amounts of the 4 base inks are printed one over the other, the resulting variations will print as new colors. Rather than having the color tones premixed like Spot Colour inks, we are basically having the inks mixed 'on the fly' on the press instead. Four Colour Reproduction is generally more expensive than Spot Colours and colour accuracy is largely dependant on the skill and professionalism of the shop printing your material. It should be noted that the colours created by 4 Colour Process printing are not solid colours at all, but rather a series of dots (see insert above). This is most noticable in the photographs reproduced in your local newspaper. Four Colour reproduction can utilize either vector based or pixel based versions of your logo (as long as the image has adequate resolution).