The simplistic position asserts that there is only one type of chakra, or at best two (major and minor).  This in fact is quite incorrect, and comes from the obscure nature of the aura and the subtle body (yogic anatomy), and the fact that the different grades, organs, strata, and so on are frequently confused and jumbled, owing to a lack of an overall systematic framework.

It seems to me that there are at least five different chakra series (and probably more).  These are:

1. The Seven Primary Major Chakras - these are archetypal and pertain to emanated levels of Consciousness and Being - the "inner subtle, causal and supracausal being.  In each of these regions or hypostases they represent the original microcosmic vertical axis ("Mount Meru"), and contain (links to) gods and major planes of existence
2. The Tan Tien ("Cauldren" for the processing of ch'i), of which there are at least three, which seem to constitute the etheric counterparts of the Primary Chakras, and are located with the body.
3. The (at least 18, if not much more) Secondary Major Chakras.  These are etheric and pertain to the subtle physical being.  They ideally constitute - or rather can be awakened into - a rhythmic microcosmic orbit (although this is very rarely the case because of congested energy flow etc)
4. The ten(?) important "chakras" (if they can be called such)  are obviously also associated with the internal organs.  Chinese medicine speaks of the five pairs (one major and one minor) of internal organs, each pair associated with specific correspondences such as an emotion, a taste, colour, cardinal point, etc etc.  These body chakras would seem to constitute a different series again.
5. A larger number of Tertiary, Minor Chakras.  These are associated with acupunture points, sensitive points in the body, etc
6. An even much larger number of Quaternary, Quinternary etc chakras (minor acupuncture points etc), associated along the meridians.