DVD discs / DVD+R Dual Layer / 2.4x printable
Dual layer are discs that stores information in more than one layer on the disc which makes it possible to store more information on it, almost twice the size compared to a regular DVD disc (8,4 GB instead of 4,7 GB). Most DVD burners manufactured after 2005 can handle Dual layer discs (often referred to as D/L) in addition to handling both Minus and Plus discs. This format is also called Double Layer and sometimes DVD-9 and is the format that most commercial movies and films are distributed on today.
Printable or Full Face printable are discs which makes it possible to make your own professional print on the top of the disc. There are no printing or information from the manufacturer on the disc (sometimes it is but very faint). To make your own printing you'll need a inkjet printer that can load discs in the same manner as you load paper in a normal printer. Such printers are very cheap today and this is the best way to make your own professional DVD discs.
Dual layer discs are also often used with Xbox 360.
Due to higher production volumes you'll sometimes find that same discs as 8x are lower priced that the discs below.