Scale wheels visualize scales and modes on the chromatic circle, showing the structure of intervals that makes up each one. The colors show the harmonic function of each note. Learn more via the following articles:

• The aQWERTYon pitch wheels and the future of music theory visualization. 
• Chromatic circles
• Scales and emotions
• Vi Hart's YouTube video on the 12 tones used in western musical scales.

ScaleWheel conceptualized by Ethan Hein, with further inspiration from Kevin Irlen's IrlenWheel.