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Key Technological Firsts

There have been a number of important "firsts" in the world of hard disks over their first 40 or so years. The following is a list, in chronological order, of some of the products developed during the past half-century that introduced key or important technologies in the PC world. Note the dominance of IBM in the list; in this author's opinion Big Blue does not get nearly as much credit as it deserves for being the main innovator in the storage world. Note also how many years it took for many of these technologies to make it to the PC world (sometimes as much as a decade, due to the initial high cost of most new technologies). I

• First Hard Disk (1956): IBM's RAMAC is introduced. It has a capacity of about 5 MB, stored on 50 24" disks. Its areal density is a mere 2,000 bits per square inch and its data throughput 8,800 bits/s.
• First Air Bearing Heads (1962): IBM's model 1301 lowers the flying height of the heads to 250 microinches. It has a 28 MB capacity on half as many heads as the original RAMAC, and increases both areal density and throughput by about 1000%.
• First Removable Disk Drive (1965): IBM's model 2310 is the first disk drive with a removable disk pack. While many PC users think of removable hard disks as being a modern invention, in fact they were very popular in the 1960s and 1970s.
• First Ferrite Heads (1966): IBM's model 2314 is the first hard disk to use ferrite core heads, the first type later used on PC hard disks.
• First Modern Hard Disk Design (1973): IBM's model 3340, nicknamed the "Winchester", is introduced. With a capacity of 60 MB it introduces several key technologies that lead to it being considered by many the ancestor of the modern disk drive.
• First Thin Film Heads (1979): IBM's model 3370 is the first with thin film heads, which would for many years be the standard in the PC industry.
• First Eight-Inch Form Factor Disk (1979): IBM's model 3310 is the first disk drive with 8" platters, greatly reduced in size from the 14" that had been the standard for over a decade.
• First 5.25" Form Factor Disk (1980): Seagate's ST-506 is the first drive in the 5.25" form factor, used in the earliest PCs.
• First 3.5" Form Factor Disk Drive (1983): Rodime introduces the RO352, the first disk drive to use the 3.5" form factor, which became one of the most important industry standards.
• First Expansion Card Disk Drive (1985): Quantum introduces the Hardcard, a 10.5 MB hard disk mounted on an ISA expansion card for PCs that were originally built without a hard disk. This product put Quantum "on the map" so to speak.
• First Voice Coil Actuator 3.5" Drive (1986): Conner Peripherals introduces the CP340, the first disk drive to use a voice coil actuator.
• First "Low-Profile" 3.5" Disk Drive (1988): Conner Peripherals introduces the CP3022, which was the first 3.5" drive to use the reduced 1" height now called "low profile" and the standard for modern 3.5" drives.
• First 2.5" Form Factor Disk Drive (1988): PrairieTek introduces a drive using 2.5" platters. This size would later become a standard for portable computing.
• First Drive to use Magnetoresistive Heads and PRML Data Decoding (1990): IBM's model 681 (Redwing), an 857 MB drive, is the first to use MR heads and PRML.
• First Thin Film Disks (1991): IBM's "Pacifica" mainframe drive is the first to replace oxide media with thin film media on the platter surface.
• First 1.8" Form Factor Disk Drive (1991): Integral Peripherals' 1820 is the first hard disk with 1.8" platters, later used for PC-Card disk drives.
• First 1.3" Form Factor Disk Drive (1992): Hewlett Packard's C3013A is the first 1.3" drive.

The source for much of this information is DISK/TREND Inc. In the 1990s, technological advances in every aspect of hard disks began coming at a fast and furious pace; it would take too long to research and list them all, so I am stopping at 1992. :^)

Next: Hard Disk Trends

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