Color is something that too many artists use without understanding
The chart above shows variations of yellow based on 3 attributes - Hue, Value, and Intensity (or Chroma).
Hue is the name we give a color - like "Red," "Blue," or "Yellow Orange"
Value is how dark or light the color appears
Intensity/Chroma is how bright or dull the color appears
There are 51 different tints, shades, and tones of yellow visible here - all of which are creating by varying the white, black, and gray balance of the color. The darker the color, the more variations you can achieve...take a moment to consume that info and consider its relevance to your practice as an artist.
Try out a chart like this in your sketchbooks. Choose a color and mix a variety of levels of white, black, and gray and chart the differences then reflect upon how this will impact the way you use color in the future.
Keep those pencils sharp and ideas fresh!