The first commercial hard disk drive weighed over a ton and stored just 5 megabytes.

IBM introduced the 305 RAMAC computer system in 1956, built around a storage unit called the IBM 350 disk drive. It used fifty spinning metal platters, each two feet in diameter, to store a then-remarkable 5 megabytes of data — roughly enough for one modern photo.

The whole unit was about the size of two large refrigerators and weighed over a ton, and customers typically leased rather than bought it, since a single system cost a substantial monthly sum in the money of the time. It nonetheless marked a turning point, since earlier computers had relied on much slower magnetic tape or punch cards for storage.