This is a good explanation. One thing to add though. With the interface of the site, you can select a colored circle and that will highlight the position where you can play the scale (or mode).
So if you highlight the red circle at the bottom, it will show you a version and position of the scale starting with the root note - A as noted above.
If you highlight the yellow circle at the bottom, it will highlight the scale/position starting with the second note and ending with the 9th. This is called a Mode.
A Mode is when you play a scale, but start or emphasize a note other than the root note. Different modes have a different sound/feel the same way that a major, minor or 7th chords has different feels.
So that is another layer to the page.
Unfortunately, I learned all of this theory, but quit playing.
So if you highlight the red circle at the bottom, it will show you a version and position of the scale starting with the root note - A as noted above.
If you highlight the yellow circle at the bottom, it will highlight the scale/position starting with the second note and ending with the 9th. This is called a Mode.
A Mode is when you play a scale, but start or emphasize a note other than the root note. Different modes have a different sound/feel the same way that a major, minor or 7th chords has different feels.
So that is another layer to the page.
Unfortunately, I learned all of this theory, but quit playing.