Back then, Sun was the biggest UNIX workstation vendor, primarily because both their hardware and baseline operating system were good and they offered a ton of flexibility in their product line.
In 1994, Sun introduced a new lineup of SPARCstation systems that had dramatically improved performance compared to their previous models — the original of which was so iconic that it defined the “pizza box” form factor for desktop workstations — and the SPARCstation 20 was one of their flagships.