Hard drives: a pictorial history

John Haanstra (top left) initiated a study of the system implications of large-scale random access. His work changed the course of the computer industry. Bottom right: the world's first data-processing system for storing computer data on magnetic disks. The system enabled the handling of transactions as they occurred. This demonstrated the path to the online, real-time applications that are so prevalent today.

Photos: Magnetic Disk Heritage Center