More than before

IBM last week set a new record for the number of bits of information that can
be squeezed onto a hard disc drive. Researchers at IBM’s Almaden Research Center
in San Jose, California, say they have created a drive with a density of 3
gigabits per square centimetre (20 gigabits per square inch) of disc
space—three times that of the best commercial disc drives available today.
The drive uses a low-noise cobalt alloy magnetic material and has especially
sensitive heads to read and write the data. The discs, which will be on the
market within three years, can store two hours of digital video in one square
inch.