Today's WSJ's Technology section ran a fascinating overview of the disk drive. The disk drive was invented fifty years ago by IBM. The first drive, called the RAMAC (random access method of accounting and control) weighed in at one ton, the disks were 24 inches in diameter, and had 5 megabytes of storage capacity.
According to the article, the capacity limit related more to the marketing department's view that no one could use more than 5 MBs than to a purely technical limit. In the last 50 years, the capacity, measured by bits per square inch, has gone from 2,000 to 135 million bits. This improvement represents an incredible 70 million times improvement.
Annual capacity increases run at 30-40% per year and the expert interviewed, Currie Mance (VP with HDS), expects storage to move from 10 GBs/one-inch drive to 100 GBs/one-inch drive over the next seven years.
While much is made of Moore's law, the related improvement in disk drive capacity is simply amazing and a true enabler of the explosion of digital media and content that is fueling the current web phenomena.