The 305 RAMAC drive could store 5 million characters (that’s right, only 5MB!) of data on 50 disks, each a whopping 24 inches in diameter. Individual bits were stored at a density of only 2Kb/sq.inch. Unlike tape drives, RAMAC’s recording heads could go directly to any location on a disk surface without reading all the information in between. This random accessibility had a profound effect on computer performance at the time, enabling data to be stored and retrieved significantly faster than if it were on tape.