The Evolution of Storage Technologies Daniel Frankl, Ph.D. Kinesiology & Nutritional Science

The Punched Card System very slow and tedious to use mistakes were easy to make recovery from mistakes was difficult Website titled “Hard Disk Drive Guide – History,” viewed 9/16/00 at

From Drums to Disk Drives “Before the disk drive there were drums… In 1950 Engineering Research Associates of Minneapolis built the first commercial magnetic drum storage unit for the U.S. Navy, the ERA 110. It could store one million bits of data and retrieve a word in 5 thousandths of a second.”

The Birth of RAMAC™ On September 13, 1956, a small team of IBM engineers in San Jose, California, introduced RAMAC™ (Random Access Method of Accounting and Control), the first computer disk storage system.

Reel-to-Reel Half-Inch Tape Drive In addition to disk storage, IBM also pioneered tape drives. In 1952, IBM had produced the first reel-to-reel half-inch tape drive--the industry standard until 1984.

Hard Drives Since the early 1950s disk drives have shrunk significantly in size and increased in capacity by more than 5,000 times. The basic RAMAC approach to storage (a rotating magnetic disk with a phonograph- like head accessing the data) remains the same to this day.

The Evolution of RAMAC After the hard disk drive was developed at IBM, many different companies began to market variants of the original RAMAC descendents. The first non-IBM hard disk drive was seen in 1980 when Seagate Technologies released their 5.25” form-factor drive, holding an amazing 5MB.

The New Size Different companies began production of the popular piece of computer equipment, among them Rodime, which produced the world’s first 3.5” form-factor hard disk drive. This new size for computer hard drives created a push for smaller, higher capacity, portable drives.

“The 3.5" Form Factor “The 3.5" form factor is the standard in the PC world today, and has been for about the last decade. Drives of this size are found almost exclusively now in modern desktop PCs, and even in servers and larger machines.

Portable Devices The only major market where other form factors hold sway over 3.5" is that for laptops and other portable devices, where the reduced size of 2.5" and smaller form factors is important.

Drive Size Compatibility Like the 5.25" form factor before it, the 3.5" form factor drives were designed to fit into the same drive bay as 3.5" floppy disk drives. These drives traditionally have used 3.74" platters with an overall drive width of 4.0" and depth of about 5.75".

The “New Age” Most 10,000 RPM spindle speed drives reduce the size of the platters to 3", and the new 15,000 RPM Seagate drive has platters just 2.5" in diameter.

The “New Age” The shrinking media size is done for performance reasons, but the 3.5" form factor is maintained for compatibility High-end drives are designed to go into expensive servers, not laptops It is no longer the case that one can tell the size of a drive's platters by its form factor

Storage Numbers One MB [Megabyte] is one million bytes, 1,000 MB make one GB [Gigabyte], 1,000 GBs make one TB [Terabyte], 1,000 TB make one PB [Petabyte], 1,000 PBs make one EB [Exabyte], 1,000 EBs make one ZB

Storage Numbers One Zettabyte can store 500 quadrillion pages of text... thus a YottaByte equals: 1,000,000,000,000,000,000,000,000 bytes)

The Future of Storage technology What’s Next? How much is enough for you?