3rd position is great for songs in minor keys and can be used in certain blues situations. Your basic starting or ending place (point of resolution) would be the 4 draw hole. The primary emphasis in playing would be the holes 4 through 6 draw. A chart is available on the Positions Chart page for determining the 3rd position key on the 12 different keys of harmonicas. 3rd Position songs page.
4th Position- With the 4th position playing style, you are no longer in the key of the harmonica, but actually in a key which is a major 6th (or nine half-steps) up from the key of the harmonica. If you play in 4th position on a key of "C" harmonica you will now be in the key of "A" (actually it would be more accurately called "A minor").
The 4th position is not quite as easy or as useful as the 3rd position or 5th position. It can be used for songs in minor keys and can be used in certain blues situations. Because the basic starting or ending place (point of resolution) would be the 3 draw hole bent down two half-steps, it is very difficult to play in this position and make it consistently sound good. The problem is that your most important note is a bent note that is very hard to always play in tune. For this reason, we recommend the 3rd position and then the 5th position for minor playing.
Occasionally, you will find folk styled players like Bob Dylan, Neil Young, or Bruce Springsteen play in the 4th position. This is because they are playing in a minor key which is the relative minor to the (major) key of the harmonica. This style is very similar to 1st position playing, but your note of resolution (tonic) is the hole 6 draw.
5th Position- With the 5th position playing style, you are no longer in the key of the harmonica, but actually in a key which is a major 3rd (or four half-steps) up from the key of the harmonica. If you play in 5th position on a key of "C" harmonica you will now be in the key of "E" (actually it would be more accurately called "E minor"). Although not quite as easy or as common as the 3rd position, 5th position is great for songs in minor keys and can be used in certain blues situations. Your basic starting or ending place (point of resolution) would be the 2 blow hole. A chart is available on the Basic Overview page for determining the 5th position key on the 12 different keys of harmonicas.