C allows any number of dimensions to be declared.

The ANSI standard states that an ANSI system must support at least 12 array subscripts.

A 3 dim array can be viewed as a book of data tables (or as cube) .

A 4 dim array can be viewed as a shelf of books .

A 5 dim array can be viewed as a bookcase filled with books.

A 6 dim array can be viewed as a row of bookcases 

A 7 dim array can be viewed as a multiple rows of bookcases

First index = Row

Second index = Col

Third index (rank) = Page number

Forth index = Book

Fifth index = Shelf

Sixth index = Bookcase

Seventh index = Row