Watch the The Major Scale online guitar lesson by Jeff Scheetz from Street Theory for Guitarists
The major scale is a 7 note scale made up from a series of whole and half steps. This scale is the basis for bulk of Western civilization's music theory. We're going to be building chords and progressions based off this scale, and we'll find other scales based on variations of this scale. All of our harmony comes from this scale; it's the most important scale you need to know to be able to understand music theory.
We're going to start by looking at its blueprint or its formula. Every scale has a blueprint of how it is made - basically a series of whole steps and half steps that is unique to each scale.