In 1956, IBM announced the first hard drive, the IBM 350 Disk File, which was designed to work with the IBM computer. The IBM 350 Disk File weighed about one ton, and stored up to 5 million characters of data on 50 spinning disks.
1970: Error Correction
With the introduction of the IBM 3330 Direct Access Storage Facility in 1970, the storage world was introduced to the concept of error correction, a technology which detect errors in data as it is being transmitted from a source to a receiver and corrects the error. Error correction is a feature in all hard drives sold today.
1980: The First Gigabyte-capacity Hard Disk
The IBM 3380, introduced in 1980, shipped with a 2.5-GB capacity, making it the first commercially-available hard drive to break the GB-capacity mark. However, the IBM 3380 weighed over 500 pounds!