What does numbers and letters define in hexadecimal color codes?

Question

Like for red hex code is #ff0000. What does ff, or 0 define here?

Answer 1

Hexa means six and decimal means ten, which stands for the base 16 number system. You’ll often hear it just referred to as “Hex”. The reason why this is usually confusing is because we’ve all learned basic math with the decimal (or base 10) number system. Hexadecimal numbers start with a pound sign (or hashtag), and are followed by six letters or numbers. The first two digits refer to red, the next two to green, and the last two are blue. You’ll define how much red, green, and blue in values between 00 and FF instead from from 0 to 255 like in RGB. A color that’s maximum red, no green, and no blue would be #FF0000. Hexadecimal colors Why do we use letters instead of numbers? Since decimal numbers can only run from 0-9, there needed to be another way to represent larger numbers. Letters replace the higher numbers. These are what the hexadecimal letters stand for: A = 10 B = 11 C = 12 D = 13 E = 14 F = 15 So the way that we get a hexadecimal number is to multiply the first number by 16 and the second number by one and add them together. Confused yet? Let's talk about the number 83. The way that you can get to the number 83 through the decimal system that we're all used to is (8x10) + (3x1) = 83. The first number is always multiplied by ten and then added to the second number. The hexadecimal number 83 is actually 131 in decimal because (8x16) + (3x1) = 131. Remember to multiply the first number by 16 and add it to the second number. Working with letters is the same. FF is (15 x 16) + (15 x 1) = 255, which is the highest number available. The number 255 should look familiar, since it's the same max value used in RGB. Once you understand these numbers you'll be able to figure out a general idea about what a color will look like based upon the intensity or red, green, and or blue. We'll wrap up with one more example. The color #7DD0D7 is a greenish blue. Check out the image below to see how to figure out what the red, green, and blue values are. By understanding what the numbers stand for in a hexadecimal color

Answer 2

numbers.here.. check this out http://m.wikihow.com/Understand-Hexadecimal

Answer 3

@www.pluralsight.com

Answer 4

Thanks Nithiwat

Answer 5

awesome answer Nithiwat! really impressive