13th September 1956
IBM introduces the IBM 350, containing the first hard drive

In 1956, IBM introduced the IBM RAMAC 305 computer. RAMAC stood for Random Access Method of Accounting and Control. It included the IBM 350 Disk File, the first magnetic storage hard drive.

The drive contained 50 double-sided 24-inch platters, each coated with a magnetic layer. All together, these platters could store around 5 MB of data.

The first IBM 305 RAMAC was sold to the Zellerback Paper Company in San Francisco and shipped on September 13, 1956. IBM's press release stated:

"305 Ramac and 650 Ramac, two electronic data processing machines using IBM's random access memory, a stack of disks that stores millions of facts and figures less than a second from management's reach. Because transactions are processed as they occur, the fresh facts held in a random access memory show business as it is right now, not as it was hours or weeks ago."

Related information:

• Newsweek: The Hard Disk That Changed the World

Image:

• IBM 305 RAMAC system
  Credit: Norsk Teknisk Museum, CC BY-SA 4.0, via Wikimedia Commons