Greetings fellow guitarists!
 
Today I am going to give a quick crash course lesson in basic theory. You will quickly notice that it all revolves around one thing in this lesson, the major scale. We will go over how this scale is formed, and how to play this on the guitar. These first few blogs are not concerned with rhythm...that will be later.
 
To begin, we will cover the MAJOR SCALE. A scale is nothing more than a way for us to organize pitches in our brains. The major scale is the basis for an entire world of other scales and chords, to be covered in future blogs.
 
Your major scale is simple: if you start on the C key on the piano (the one just to the left of any group of 2 black keys)
 
 

 
 
 
 
 
 
 
 
Or if you start here on a guitar
 
 

 
 
 
 
 
 
 
 
 
And you play each white key, going from left to right, until you reach another C
 
 

 
 
 
 
 
 
 
 
You have just played 8 notes, or one OCTAVE. This is also why there are only the letters A through G used; with 7 possible pitches in the major scale before you return to the original pitch, you only need 7 letters. On a guitar it looks like this:
 
 

 
 
 
 
 
 
 
 
 
If you prefer tab, there will be a tablature section added to the end of this blog. There will also be a future blog covering the scale positions all over the fretboard. So don't *fret* just yet ;)
 
And that is your C major scale. You may now be asking, "Why does it sound like that?"
 
As mentioned before, a scale is nothing more than a PATTERN. Your major scales follow a pattern described by INTERVALS. An interval is a certain amount of difference between two pitches. In most western music, we describe intervals in terms of STEPS. For instance, the difference between C and the next note in the scale, D, is one WHOLE STEP. Like this:
 
 

 
 
 
 
 
 
 
 
A HALF STEP occurs between the 3rd note of the scale, E, and the 4th note, F. Like this:
 
 

 
 
 
 
 
 
 
 
Now, the way these intervals are arranged define different scales. In the major scale, it goes like this:
 
-- = whole step, | = half step
 
C -- D -- E | F -- G -- A -- B | C
 
You will notice that there is a half step between the 3rd and 4th notes (E / F) and the 7th and 8th notes (B / C). This is how a major scale is defined.
 
On a guitar, this is extremely easy to see. Each fret represents a half step. In the figure above, playing the 5th string / 7th fret followed by the 5th string / 8th fret is exactly a half step. To achieve a whole step, you simply move two frets instead of one, as in the example before the last one.
 
Once you understand this, you will begin to see that on a guitar, you can create ANY scale in ANY key simply by changing the order of your whole and half steps, and starting on different notes. That's a future blog though.
 
That's it for this blog! I hope to update it in the future with a video and an actual tablature section. Until then, adios!