I was the only female sitting across a large conference room table recently, I didn't know it but I was about to give a lesson onPMS. I began to present one of my projects and explained how it was being done in one PMS color. (In my corner of the world PMS stands for Pantone Matching System.)
In order to address the confused looks I continued to clarify that PMS is a spot color system used to manage and control color accuracy in the printing process. A quiet laughter ensued as I went on to explain how Target uses a Spot PMS color. Gosh, could I not have picked Red and a Target to explain Spot PMS. I can't stop laughing about it when I think back on my choice of words and visuals. 3 decades ago when I first learned what this color system was I laughed about the acronym but on this day I was completely oblivious to what everyone across the table was thinking.
So the lesson for those who want to know: picking a PMS color is like picking paint chips at the hardware store. You choose the swatch by number and then the color is pre-mixed for you at the store before you paint. The same applies to Pantone colors and it is good for 2 applications in printing; one is in offset printing jobs that are one (or two) color and second as an additional color to the 4 color process for accuracy of a specific color, like your logo, which should not vary in tones and hues on the various printing applications. Full color, offset (professional) printing is normally a 4 color printing which is CMYK. CMYK stands for Cyan, Magenta, Yellow and Black. However, a large press can accommodate a 4-color project plus any additional PMS colors if necessary creating a more complex but accurate 5 or 6 color project.
Pantone was developed in 1963 for designers as a tool to communicate color by referencing a number to the printers. Prior to Pantone each ink company had their own color combinations and there was no way to correlate "Candy Apple Red" from one ink company to another. Now 186 red is consistent from designer-to printer-to ink maker-to the deliverable. Initially the Pantone formula guide books had 747 different colors. Today's Pantone Matching System features 1,114 distinct color formulas that are exact across the board. Target for example uses PMS 186 Red.
If you are very picky about a color and it's appearance across your brand you should ask for a PMS color and let all of your vendors know that number. This will insure when they are printing your direct mail promotions at one vendor and your business cards at another vendor, all your collateral materials will be printed at the same color and consistency.