How to read HEX color codes?

A hex color code is a code that describes a color in HTML, CSS, SVG and other web technologies. It is a way to describe an RGB color. An RGB color is a way to describe a color using values describing the amount of Red, Green and Blue the color is composed of.

In color codes, the values for each base color is described using a single byte, or a numerical value between 0-255. The lowest value, 0, describes an absence of color and 255 describes the maximum amount of color. An example of a representation in decimal is the color rgb(250, 128, 114), a light red salmon color.

Hex color codes similarly describe numbers, but are composed of hexadecimal numbers. A hexadecimal number is a number system with sixteen (0-F) numbers instead of the ten (0-9) numbers in the decimal system we usually use. The numbers that follow $9$ in hexadecimal are $\texttt{A}$ for $10$, $\texttt{B}$ for $11$, and continuing until $\texttt{F}$ for $15$. Similar to the decimal system where the number $543$ is actually $5 \cdot 10^2 + 4 \cdot 10^1 + 3 \cdot 10^0 = 543$, in hexadecimal the number $\texttt{38B}$ is actually $3 \cdot 16^2 + 8 \cdot 16^1 + 11 \cdot 16^0 = 907$.

Hex color codes are composed of six hexadecimal characters, where each pair of characters corresponds to a color value in the range 0-255 or in the hexadecimal range 0-FF . For example for the salmon color, #FA8072:

1. Red: $\texttt{FA}_{hex}=250$
2. Green: $\texttt{80}_{hex}=128$
3. Blue: $\texttt{72}_{hex}=114$

Some examples of hex color codes:

1. #00FF00 rgb(0, 255, 0) - Most vivid green possible
2. #000000 rgb(0, 0, 0) - Absolute black
3. #FFFFFF rgb(255, 255, 255) - Absolute white
4. #915C83 rgb(145, 92, 131) - Antique fuchsia