I’ve written about the importance of knowing Major scales. So much of theory (chords, scales, etc. etc.) relies on a sound knowledge of major scales. While a lot has been written on being able to play major scales up and down the neck in different positions and keys, a very effect way of learning major scales from a knowledge point of view is to learn all 12 major scales in the open position.
Playing scales in the open position is often seen as a beginner’s approach to scales. While this is somewhat true, it’s important to realize that playing scales in the open position can be sometimes technically more difficult than across the fretboard and usually requires a greater knowledge of the scale itself. When you learn a movable scale shape, it becomes very easy to change keys by simply moving the shape around the fretboard. This is not the case with open position scales. For example, to be able to play all 12 major scales in the open position, you need to learn each scale individually.