The pentatonic scale is a five note scale. The major pentatonic scale is taken from the full major scale,
but is missing a few notes.
This makes it easier to play than the major scale, and a bit more melodic as well, although that's not
always the case.
Let's compare the major scale and the major pentatonic scale.
Here's the difference in pictures.
As you can see from the picture above, the 2 notes that are missing from the major scale are the 4th and 7th notes, giving us a step pattern of Tone, Tone, Tone and a half, Tone and then a tone and a half again.
The pentatonic scale is a lot easier to play than the major scale, but I've found that the best thing is to know both scales well, as some pentatonic patterns fit nicely in other positions of the major scale.
If that sounds like gibberish to you, dont worry, it'll become clearer as we go along.
The most common pentatonic scale pattern on guitar
The A minor pentatonic scale uses the same notes as the C major pentatonic scale, the only difference being the starting point.
If you play from C to C, it's C major, and if you play from A to A it's A minor.
The finger positions shown here can be changed for whatever works best for you, but if you want to stick to the one fret per finger rule, then what I've drawn here is the way it should be.
Lots of people play pentatonic scales without using the fourth finger. Sometimes it works better that way.
How the A minor pentatonic fits into the natural A minor scale
Here I've colored in the pentatonic notes in purple to show the real relationship. It helps to keep the major pattern in mind even though you're not playing the full scale as this gives you a good reference as to what chords work well. Soloing over an A minor chord works great here, but a D minor chord, for example, would sound a bit off even though it's in the key of A minor. It's for reasons like this that I'm glad I learned the major scales first. Pentatonic patterns are still very melodic though, and in rock music where most of the chords are power chords, it can really work well.
The C major pentatonic guitar scale.
This scale starts at the 8th fret, so it fits onto the end of the A minor scale. As can be expected, it works great over a C major chord. If you superimpose a C major Barre chord over this pattern, it becomes quite obvious.
As you might have recognized by now, this is the same as the third finger pattern of the C major scale
How the C major pentatonic fits into the natural C major scale
Here again we've got the pentatonic notes in purple. The reason I'm showing you this, is because the pentatonic patterns also fit well over different C major scale patterns. For example, This pentatonic scale pattern also fits well into the very first C major scale fingering, but it wouldn't actually be the C major pentatonic because the notes would be different. That's great for finding scale patterns that fit nicely with specific chords, and it's something you should look at, and experiment with. Anyway, here's the actual pentatonic to major relationship in the key of C.
All five pentatonic scale patterns
It's a good idea to familiarize yourself with each pattern one at a time. Memorizing five patterns is a lot easier than trying to memorize the entire fretboard.