Guitar Chords and Scales.
If you take a guitar and play your way up the fretboard, you'll find that the notes repeat themselves in higher or lower versions every 12 frets. Prove this by playing an open low E string, followed by the 12th fret of the low E. Notice that both notes blend together with a matching pitch, as both are E notes, yet one is much higher than the other because they each belong to a different group of 12 notes. The guitar, and almost every other instrument, lets you play higher or lower versions of a cycle that containes only 12 different notes.
The first note in a scale is also known as the root or the tonic. The other notes are simply referred to by their position in the scale, so the second note is called "the second" and the third note "the third". Note how the third is different in the major and minor scales, so the two different notes are a "major third" and a "minor third". The numbers on the two charts below reflect these names; they are from the scale's group of 7 and not from the larger group of 12. You can click either image to have a closer look, and read more explanation below the images. Don't worry about the letters below the chart for now.
Notice the names of the strings on the left, beginning from the bottom with E (the thickest string and lowest in pitch) followed by A (the second lowest in pitch) and on up to the high E. Have a look at the first "4" on the low E string. Notice that a "4" also occurs on the open A string, at a five-frets distance away from the E string's 4. This is because the A string is tuned to match the fifth fret of the E string. Every other pair of sequential strings is tuned to a five-fret difference (a major fourth), with one exception: the G and B strings. These are tuned to a four-fret difference, in order to make the total distance from low E to high E into 24 frets or two octaves, which makes chords a lot easier to play. You can see a more detailed map of the fretboard if you like.
How to Use the Guitar Charts.
First of all, you can download the basic charts and key selectors here.
If you're not into .pdf files, you can save all the images linked from this page and print them however you like.
Begin by choosing a key or a tonic for the scale. Place the key selector / fret marker so that it shows the proper key in the lower left, and adds the fret numbers or markings, whichever you wish. For example, if you use the selector to show "Key of D", you will see a "1" on the D string showing that the tonic of the D scale matches that open string. You'll also see the shape of a D major chord in the bolder, larger numbers that mark notes used in chords. Major and minor chords use the root, the 3rd and the 5th, which are the most essential notes of the scale.
The image below shows the key selector in action. There is also a selector with fret numbers instead of markings; print the one you prefer, cut out the window, and place it over the chart of your choice to use as a practice aid.
To play a scale from these charts, simply start with a 1 and count up to 7, then add the next "1", which is the 8th note that gave the octave its name. It's up to you when to find the next number on a different string, and you can highlight the ones you wish to use if you like. It's also up to you which fingers you'd like to use; just make sure you use all four. To play a chord, hold down the bold-numbered frets and strum. You'll see some familiar chord shapes, and some unfamiliar ones, as you explore these charts.
Alternative Scale Types.
The six scales in the table below will offer a wide range of melodies and harmonies.
The Seven Modes.
The modes are variations on the diatonic pattern of the major scale, starting at
different places in the TTSTTTS cycle. Major and natural minor are both modes
in themselves, and there are also five more as listed below.
In time I also hope to add notes on dexterity-building exercises, finger-picking technique, strumming patterns, reading music, and a section for tabs of some favorite songs. This will happen as my own learning progresses and as time permits. In the meantime, these charts should be really useful for anyone who wants to learn their scales and develop their ability to improvise. There's also a blank tab sheet to figure out cover songs with. Have fun!