What is the difference between RGB and CMYK. What is Pantone Color?
RGB and CMYK are colorspaces that are used with specific imagery (raster or vector). As CMYK is the color of inks used in printing and RGB is the color of the light emitted from a computer screen, each colorspace has a particular use. CMYK is generally used for producing prints and photos (where such can be easily manipulated by adjusting tones, contrast and mixing through a color palette prior to setting up a print job) while RGB is used for viewing images on screen, vector or raster types.
Pantone color refers to an elaborate palette system consisting of unique codes assigned to every color and its shades in existence (presumably). There are a total of 1757 unique and individually numbered colors and one could look these codes up online in order to find out the name of a specific shade. This is useful for hard printing (banners, posters and fabrics) applications that require specifications on color shades.
A similar system to Pantone is the Hexadecimal color code, which also carries digits for every color in existence (again, presumably). These codes can be also looked up online and used in most Adobe programs through their color palette to obtain a specific hue. In my experience, I frequently use Hexadecimal colors to get exact shades for logos and webpages from images to associate with a certain look aesthetically.