PMS stands for Pantone Matching System. This is recognized globally in most if not all industries from fashion and textiles to advertising. Often referred to as Spot Colors, PMS colors are custom mixed inks created by the Pantone corporation. They can be more intense since they are an opaque ink unlike transparent processed color inks. They can also include metallics, florescent, pastels and other colors you cannot create with CMYK.
It is recommended for print/textile production with limited colors, the great if not brilliant thing about PMS colour is you get exactly the color you expect.
The not so pleasant parts are, it can be expensive, printing charges are usually based on on the number of inks being used, and you’ll be limited to 6 at the most. It gets pretty pricey once you’re using more than 4 colors.