iPod technology behind Nobel Prize for physics

Albert Fert and Peter Gruenberg won the 2007 Nobel Prize for physics for work that has allowed hard disks to be made much smaller for everything from laptops to iPods.

Here are some facts about the technology:

* The prize was awarded for work on magnetoelectronics, also known as spintronics.

* It uses the spin of the electron to store and transport information instead of the electrical charge, meaning much more information could be kept in a smaller space than before.

* Fert and Gruenberg made independent discoveries of the giant magnetoresistance phenomenon, considered the birth of spintronics, in the late 1980s.

* They found weak magnetic fields force large changes in electrical resistance. That allows the conversion of data stored magnetically into electric signals the computer can read.

* The technology allowed the development of handheld devices such as iPod music players and mobile phones with lots of functions.