What? How is a CD or a flash drive not "light" based?

The world's first entirely light-based memory chip to store data permanently has been developed by material scientists at Oxford University. The device makes use of materials used in CDs and DVDs, and it could help dramatically improve the speed of modern computing. Today's computers are held back by the relatively slow transmission of electronic data between the processor and the memory. There's no point using faster processors if the limiting factor is the shuttling of information to-and-from the memory. The researchers think using light can significantly speed this up.

Read more in Nature and Youtube.