Ever wonder how HTML color codes are put together? For the beginner, it can look like lots of numbers and letters that make no sense. In reality, HTML color codes are written that way for a specific reason that we'll look at in this article.Introduction to the Hexadecimal SystemIn mathematics, the hexadecimal or simply hex is a numeral system with a base of 16 usually written using the symbols 0-9 and A-F. The numbers 0-9 have the same value as in the decimal system but starting with the letter .