If you’ve ever played Guitar Hero or Rock Band on guitar before, you may have noticed that lower notes seem to be green, and higher notes seem to be orange (or blue on Medium, or yellow on Hard). The green note is indeed supposed to represent the lowest notes in the riff, whereas each consecutive note represents a higher note. Of course, a lot of riffs also include chords, which would be charted as two or three different colors. The same principle applies here, a green/red chord would be the lowest, and a blue/orange chord would be the highest. There’s also riffs that use more than five notes, requiring what’s known in authoring terms as “wrapping.” The RBN docs explain this in great detail, and is generally a really good resource for learning the basics of authoring and how a chart should work.

Did you ever played Guitar Hero or Rock Band on guitar before? (or, at least, did you saw someone playing?)