So, what is the different between a digipak and a CD case?
Although cheaper to make, due to the 'exclusivity' and 'collectability' of the digipak, it often costs more to buy, as fans see them as a collectable item, and it is more aesthetically pleasing.
Below is the typical design of a cd case, with 4 main areas, then the spine on the outside also.
Below here is the typical layout of a digipak, as you can see it has 6 printable surfaces and all are made of card.
Along with both, there will usually be a booklet, filled with pictures within the theme, or lyrics and production information.