Neither computers nor the storage devices were mass-produced items in the early days of computing. Information processing systems were available at specialized facilities only. Computers started emerging as a system used by a wide range of people in the beginning of 1980s. Development of desktop computers was the beginning of the new era of information technology. This form of computers initiated a new demand in the data storage industry. Need for DASD with physical dimensions suitable for desktop computers became evident and hard disk drives with 51 4 disks emerged. This was also the first non-IBM HDD product; the ST506 series (storage capacity 5 MB) was introduced by Seagate Technology, a company founded by an ex-member of the IBM family, Allan Shugart. For desktop market, ST506 drives were shipped with 4 disks, but drives for large storage requirement used to have up to 16 disks. An entire drive bay of the original IBM PC was required to house one ST506. Comparing to today’s standard, these drives were primitive. But they opened a new world of volume storage on PCs. The ST506 series used stepper motors to move the read/write head positioning actuator. It was early 1980’s when the first 51 4 inch drive with voice coil motor (VCM) actuator used in today’s HDD was produced in volume, but stepper motor drives continued to be present for few more years.
The first HDD with 31 2 inch disks came from a company named Rodime in 1983. These drives started as a device on a plug-in expansion board. The drive was on the controller card which eventually evolved into IDE (Integrated Device Electronics) HDD, where the controller was incorporated into the printed circuit board (PCB) on the back of HDD. Quantum Corporation made the first IDE drive in 1985. The first 31 2 inch HDD with VCM actuator was volume produced by Conner Peripherals in 1986. In the same year, PrairieTek shipped the first 21 2 inch drive. However, the 51 4 inch drives continued to dominate the market until the late 1980’s or early 1990’s. Large number of competitors emerged to produce HDDs for the growing PC market. The 51 4 inch drives started to be phased out giving space to 31 2 inch and 21 2 inch drives, the later targeting the growing laptop market.