A Tohoku University research team at the Institute of Multidisciplinary Research for Advanced Materials claim to have developed a DVD that is capable of holding 42GB of data, or nearly 9 times as much as a standard DVD. The Japanese researchers achieved this feat by using V-shaped as opposed to flat pits on the DVD's recording surface, which allows for more data-recording space. The same method can be applied to CDs as well.
In comparison, a single-layer Blu-ray disc can hold 25GB, but the researchers say their method cannot be applied to the blue-laser discs. Also, current DVD players would not be able to read the content written to the super-capacity discs.