Apologies if i've posted this in the wrong forum.

I've been teching myself some basics on scales and have a few questions.

Why are scale shapes named with a letter, e.g. E shape, D shape? What relation does the shape have to that letter/note?

What is meant by 'chord tones'?

What exactly is meant by a 'key'? In Total Guitar they mention songs being in the key of say B and list chords in that key. How do you work out what key it is in?

What is CAGED?

1) Calling a scale "D" shape or "E" shape is to do with the chord shape at that point, which is derived from the "CAGED" system. E.G. If the root note of the scale is on the E string, it is in E-shape, and the E shape bar chord is played in that position also.

2)"chord tones" are the notes that make up a chord (or that are contained within a chord).

3)"key" is to do with the tonal centre. If you're playing chords created from an E major scale, and soloing with an E major scale, you are in the Key of E major (because everything relates to E major).

4) The chords of, say C major, are basically the chords made from notes in the C major scale. This applies to all keys.
try reading zeguitarist's ultimate guide to guitar. he explains everything really well.
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