computerhistory.org
The First Disk Drive: RAMAC 350 - CHM Revolution
The First Disk Drive: RAMAC 350Computers hold thousands of data records. Imagine if finding the one you wanted required starting with the first, then going through them in order.High speed, random access memory—plucking information from storage without plodding through sequentially—is essential to the way we use computers today. IBM’s RAMAC (Random Access Method of Accounting and Control) magnetic disk drive pioneered this ability. The RAMAC 350 storage unit could hold the equivalent of 62,500 punched cards: 5 million characters (about 3.75 MB).