A digipak is a way
of distributing your CD by using multiple panels on your packaging to look more
attractive to an audience; normally the images used are related to the
artist/band. This is a clever way
to promote your band/artist because the images can create a better branding. Inside will usually
contain details of the producer, artist/band and some times, within the booklet
inside is the lyrics to the songs on the CD.
(Below)
This is the Gorillaz digipak for 'Demon Days' which was a great success and in my opinion their best album. It consisted of images of the four digitally animated characters faces on each panel; the outside of the panel was a serious face for the character and the inside was almost like their alter egos.
These are a few templates for the digipak's we could make, although we have to construct a 6 panel digipak. This is a six panel digipak but there are many different template we could use, this is one of the most commonly used. 
The second template isn't as common because a digipak is usually used for limited edition or 'best of' albums, meaning they contain at least 2 disks. A lot of design ideas would have gone into the construction of the images and colours to gain a bigger audience. 
This is also a very commonly used template because it can display the artist/bands branding images and secure a detailed overview of the album within a booklet maybe or on the cover itself. Overall, I would say although this is a simplistic and common design, it's one of the better to use because it's 'short and sweet' with attracting an audience.