A little history, back when RISC was the up and coming thing,
SUN wanted one, but no one had one for sale. So they made one
up. Originally known as Sun Processor ARChitecture, it was not
actually a chip per se, but a specification (SUN not owning
fabrication plants). Several chip manufacturers, notably
Texas Instruments and Cypress (later Ross Technologies)
actually produced the chips.
Bill Joy from Sun and Dave Patterson from Berkely started work on
the SPARC architecture in 1984. In 1986 they produced they
the version 7 spec (32 bits) which was then made into the first line
of SUN workstations, the SUN 4/xx0 line of workstations.
The line has been updated several times over the last 18 years.
SuperSPARC and SuperSPARC-II is a superscalar version
of the original 32 bit CPU. Ross produced the hyperSPARC
which had a faster clock (200Mhz vs. 85Mhz in the SuperSPARC).
Also the microSPARC was produced (being a cheaper, less powerful
cpu similar to Pentium vs. Celeron or Athlon vs. Duron)
Finally there are the 64 bit versions. SPARC64 produced by
Fujitsu (who actuall owned Ross for awhile) focused on
out of order execution as opposed to Sun's chosen one, the
UltraSPARC. The UltraSPARC did not do out
of order execution arguing that memory latency would negate
the benefit. What it did add though was a set of graphics
operations (like MMX or HP's MAX on their PA-RISC).