For businesses, accurate color reproduction is essential for brand recognition, brand perception, and reputation. IBM's blue and T-Mobile magenta are pretty iconic. It would look pretty silly if you had a meeting with IBM and the business cards you got handed all had a different shade of blue and none of them match the letterhead on the meeting agenda the provided. Or you walked into a T-Mobile store and the magenta on the walls didn't match the placards, the floor, the employee uniforms, nametags, or the sign hanging in the window.
There are color calibration devices, like the color scanner in the paint section at Home Depot, that are used to calibrate monitors, printers, and everything else but they're useless without a reference point to calibrate to. That's where Pantone comes in. Pantone produces a standard catalog of colors that people can reference. Additionally they license the catalog to software and hardware manufacturers for color matching purposes.
When you take a Pantone color swatch and pull out a color, open Photoshop and paint a swatch of that color and print on an Epson Pantone printer and an HP Pantone printer, those prints are going to match the swatch from Pantone.
Pantone sells consistency.
All devices have different ranges of color they can reproduce and nothing can produce the full CIE colorspace. Even if we possessed a device with that capability, we lack the ability to describe all possible colors to that device. AdobeRGB and sRGB are subsets of CIE and computer monitor makers struggle to make professional grade monitors that can cover 90%-100% of those gamut ranges.
The Pantone system is constrained further by just being a subset of colors exist within a limited gamut range. Pantone colors are only ones that can be produced by the mixing of, I think, 14 base colors. Their system sets clear limits on the scope of the problem and provides clear and consistent reference points.
http://www.pantone.com/graphics/pantone-matching-system?from...
You have different books for "Matte" and "Glossy" and also one for "Fabrics".