This is the 4th form of 5 in the basic major scale pattern series. This major scale pattern is commonly used since it is contained in a 4 fret span; making it easy to play with the 4 fretting fingers.
Scale Patterns are moveable scales where fingerings don't change from key to key. The root note (green dot) names the key of scale. What does this actually mean? It means you simply learn this pattern and you immediately know all 12 keys. You just need to place it on the correct fret to play the scale in a particular key.