September 14, 1956
IBM RAMAC 305 announced
IBMInternational Business Machines — a major computer and enterprise technology company since the early 20th century. announced the RAMAC 305 on September 14, 1956 — the first commercial computer with a hard diskMagnetic storage with spinning platters — the primary bulk storage for PCs and servers for decades. drive, storing 5 million characters on 50 platters.
What it was for
The RAMAC's 350 disk storage unit replaced punched cardA stiff card with punched holes encoding data or instructions — an early program and data input medium.s and magnetic tapeSequential storage on coated tape — used for backups and archives when disks were too costly. for online random access to data. Random-access disk storage became the foundation of every database, file system, and server farm — from mainframes to cloud SSDs.
Companies
- IBM
Why it's here
RAMAC introduced the hard diskMagnetic storage with spinning platters — the primary bulk storage for PCs and servers for decades. drive as a commercial product.
Why it mattered
Random-access magnetic storage changed how computers kept and retrieved data online.
What it solved
Batch systems needed faster access to records than sequential tape could provide.
Media
ImageIBM 305 RAMACNorsk Teknisk Museum, CC BY-SA 4.0, via Wikimedia Commons
Related
- Whirlwind magnetic core memory operational1953
- IBM System/360 announcedApril 7, 1964