CMYK printing is the standard in the industry. The reason printing uses CMYK comes down to an explanation of the colors themselves. CMY will cover most lighter color ranges quite easily, compared to using RGB. This gives CMY a much wider range of colors compared to just RGB.
The use of CMYK (cyan, magenta, yellow, and black) for printing has become kind of a trope for printers. But the reason why printing uses CMYK is not that well known, even to many graphic designers.
On the surface, it do not seem to make sense. You might even have learned in elementary school that the primary colors — red, green, and blue (RGB) — are the primary colors, from which all the other colors come. After all, monitors, projectors, and television sets use red, green, and blue (RGB) to create all the other colors. Mixing some of these colors produces the secondary colors — cyan, magenta, and yellow. Mixing them all produces white.