The Major Diatonic is the standard Blues tuning and may be played in the 1st & 2nd Positions (Straight Harp & Cross Harp).
The original style of playing, known as 1st Position (Straight Harp), is suitable for playing simple melodies, Folk music and various other types of music that call for melody lines, along with some chords. 1st Position (Straight Harp), is still used by many players today, but due to its simplicity of sound, it is not as popular as 2nd Position (Cross Harp).