When you create global colors from scratch, you can set these to be spot colors.
In professional printing, spot colors can be used instead of CMYK process colors when your artwork contains a very limited color set. By setting these colors to be spot colors, print costs can be reduced significantly. You may also be able to accurately reproduce colors otherwise impossible with process colors.
As well as setting a global color to be a spot color, you can use pre-supplied PANTONEĀ® colors, which will automatically become a global spot color in the Color panel's Swatches section's document palette when applied.