
1948
1949
1950
1951
1952
1953
1954
1956
IBM 305 Ramac
IBM introduces the 305 RAMAC (random access method for accounting and control), the first magnetic hard disk storage system. The RAMAC stores 5 megabytes (MB) of data, is the size of two large refrigerators, and costs $10,000 per MB. The device can store five million characters of data on 50 disks, each 24 inches in diameter. Each disk can hold the equivalent of 25,000 punch cards.
1958
1960