The Major Scale in Chords is a progression of chords in a major key. The intervals between each chord in any major scale are as follows:
Root chord major; up two frets and minor; up two frets and minor again; up one fret and major; up two frets and major again, up two frets and minor; up one fret and diminished; up two frets and major (back to your root).
These are all the chords in that key. So for Cmajor, you would play C, Dm, Em, F, G, Am, Bdim, C.
Examples of this include "Like a Rolling Stone" by Bob Dillon. If you number each of the above chords in order, the chords for the vers of this song are: 1, 2, 3, 4, 5.
Red hot Chili Peppers "Under the Bridge" verse could be written down as 1, 5, 6, 3, 4, which would mean E, B, C#m, G#m, A.
The beauty of this is that once you know the intervals for a song, you can very easily transpose it to a different key to suit someone's voice for instance.
Mix and match these chords to get a feel for how many, many songs are written. For more colour and effect, you will need to learn the jazz alternatives to these chords and also learn how to change key using the circle of fifths and diminished relations between keys.
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