In 1978, Alan Shugart met Finis Conner at Memorex. Conner had a great idea: to build a hard drive the same size as a 5.25" floppy drive but with 15 times the capacity and 10 times the speed. At this time people were beginning to buy a lot of PCs with several floppy drives and needed more and more storage capacity.
In 1979, they founded Shugart Technology. The company was soon renamed Seagate Technology because Xerox which acquired Shugart Associates, a floppy drive company also founded by Shugart in 1975, would sue them over the name.
One year later, they introduced first small hard disk drives which packed 5 to 10 MB of storage, they sold thousands of them, mainly to IBM for their mainframe. Within a few years, they had produced 4 million units.
The same year, Shugart Associates defined the specifications of a new interface using a device-independent parallel connection and allowing to attach several peripherals to a same desktop computer. This interface was called SASI (Shugart Associates Systems Interface). In 1982, NCR added features to Shugart's original interface which was renamed in SCSI (Small Computer System Interface) and then widely used, particularly by Apple.
In 1981, several of the engineers who worked on SASI left Seagate to form Adaptec, a host card manufacturer. Finis Conner also left the company in 1984 and launched Conner Peripherals.
For more than 15 years, under Shugart leadership, Seagate was the first hard disk manufacturer. In 1997, the company employed 100,000 people worldwide with a $9 billion turnover. Sadly, one year later, the company lost more than 650 M$. The lost was inputted to Shugart who resigned from Seagate Technology's board in August 1998.