In this lesson we have to learn more of theory. I hope 
you still remember that there are several notes in music: 
C, C#, D, D#, E, F, F#, G, G#, A, A#, B. You should 
also know where you can find particular notes on your 
fretboard:

E||-F-|----|-G-|----|-A-|----|-B-|-C-|----|-D-|----|-E-|-F-|----|-G-|
B||-C-|----|-D-|----|-E-|-F-|----|-G-|----|-A-|----|-B-|-C-|----|-D-|
G||----|-A--|---|-B-|-C-|----|-D-|----|-E-|-F-|----|-G-|----|-A-|----|
D||----|-E-|-F-|----|-G-|----|-A-|----|-B-|-C-|----|-D-|----|-E-|-F-|
A||----|-B-|-C-|----|-D-|----|-E-|-F-|----|-G-|----|-A-|----|-B-|-C-|
E||-F-|----|-G-|----|-A-|----|-B--|-C-|----|-D-|----|-E-|-F-|----|-G-|
O           III       V      VII      IX            XII          XV 

"You noticed for sure that there are many places on 
guitar neck to play for example A note. Some of them 
are exactly the same pich - others sound different. They 
are still A notes but played on different pitch"

I'll try to describe it to you. All notes (from C to B) are 
arranged in octaves:

1st octave: C1, C#1, D1, D#1, E1, F1, F#1, G1, G#1, 
A1, A#1, B1
2nd octave: C2, C#2, D2, D#2, E2, F2, F#2, G2, G#2, 
A2, A#2, B2 and so on... For example C2 is higher note 
than C1 and C2 is lower note than C5.

In standard tuning notes on the fretboard start with E3 
(thats the sound of open low E string):

E3||F3|---|G3|---|A3|---|B3|C4|--|D4|---|E4|F4|---|G4|

On the above diagram I have shown you how the notes 
are arranged on the thickest string (on its first 15 frets). 
Now lets look at first 15 frets of A string:

A3||---|B3|C4|---|D4|---|E4|F4|---|G4|---|A4|---|B4|C5|

If we will compare this two strings...:

A3||----|B3|C4|---|D4|---|E4|F4|---|G4|---|A4|----|B4|C5|
E3||F3|----|G3|---|A3|---|B3|C4|---|D4|---|E4|F4|----|G4|
 0             III      V      VII     IX          XII          XV  

and use rules that we have learned in previous lesson 
("we can find the same note on first three strings..." and 
so on) we will be able to end this diagram by adding rest 
of the strings to it. We will be also able to add the rest 
of the frets to it. Do it now! If you can't - you have to 
begin from the beggining of previous lesson. After doing 
this diagram you can read the rest of this lesson :)

-----------------------

Now we have to understand what an interval is. "An 
interval is the distance between two notes." Basic 
intervals are:

- unison
- second
- third
- fourth
- fifth
- sixth
- seventh
- octave

"The basic intervals may be thought of as the letters of 
the musical alphabet. A unison is the interval between 
notes of the same letter (A-A). A second is the interval 
between adjacent letters like A-B. A third skips a letter: 
E-G. A fourth skips two letters: D-G and so forth."

Let's see some examples:

Ex. 1 - Unison is the interval between two half notes 
in first bar of this exercise.

Ex. 2 - Second is the interval between two half notes 
in frist bar of this exercise and between two half notes 
in second bar of this exercise.

Ex. 3 - Sixth is the interval between two half notes 
in first bar of this exercise.

Ex. 4 - In This example you will find more examples of 
basic intervals (remember that for example seventh is 
the interval between 15th fret and 1st fret - not between 
15th and 14th fret).

Ex. 5 - This example is the repetition of rules that we are 
using to find the same notes on different strings. It is 
"builded" by the same notes but played on different 
strings than Ex. 4.

Ex. 6 - I told you how to make Power Chords few 
lessons ago. Now I'm going to show you much more 
professional method. You want to know how musicians 
builded Power Chords? They connected two 
notes with some interval between them. Listen to 
example and guess witch interval was it?

Ex. 11 - Yes - the interval between those two notes 
from which They've made Power Chords is a fifth. Look 
at the rest of examples. Remember that we are building 
Power Chords in two steps:

a) first we have to choose any note that we can find on 
the fretboard
b) than we have to find second note; there has to be 
an fifth interval between our two notes

And this is it! We have our Power Chord. 

Ex. 12 - And how did they build Power Chords played 
on three strings? Let's take a look. The interval 
between the highest and the lowest note should be an 
Octave.

WoW. You have learned (I hope so) so many things 
during our 6th lesson! Remember - you have to learn all 
this stuff! Practice a lot before downloading 7th Part of 
School!