One of the most efficient ways to memorize scales and play them on the guitar is using box patterns. These are ways of 'mapping' the scale across the guitar fretboard, creating fixed shapes that can be transposed to play the scale in a different key. They are particularly helpful for improvisation, and once they are memorized, they serve as an excellent aid to understand the visual and auditory relationships between intervals. Select a root note to see a list of box patterns for the pentatonic scale:
The pentatonic scale, as it name implies, it's made up of five notes instead of the regular seven (such as the minor/major scale and the greek modes). For study purposes only, the major pentatonic scale may be thought of as an incomplete major scale, though it is crucial to understand that the pentatonic has a unique character and it is a complete scale per se. Taking any major scale and removing the fourth and seventh degrees will result in what is traditionally known as a major pentatonic scale. Thus, the C pentatonic major scale is made up of the notes C, D, E, G, and A.
The term 'pentatonic' may be understood in a broader sense: any scale that's made up of five notes is technically a pentatonic scale. They occur in traditional and folk music from West Africa, India, Asia, South America, Eastern Europe, the nordic countries, etc. Scales strikingly similar to the western major and minor pentatonic are found throughout most cultures, and this pervasiveness has been the subject of numerous studies. This peculiarity makes the pentatonic scale an useful resource for creating an eastern sound when writing melodies or improvising. The pentatonic scale has seen numerous uses in musical education, playing an important role in the first stages of the Orff, Kodaly, and Waldorf methodologies. The fact that it is almost impossible to incur in harmonic 'mistakes' when improvising with it, together with its intuitiveness and its flexibility in harmonization make the pentatonic scale a very useful teaching tool.