SCO can refer to two separate computer companies:
The first was the Santa Cruz Operation, which made SCO Unix, a computer operating
system, from the 1980's till 2000. In 2000 they sold their Unix holdings and renamed themselves Tarantella, Inc, and were eventally bought out by Sun Microsystems.
The second is The SCO Group, which until 2002 was known as Caldera International, but changed their name after acquiring the Later company's Unix
system. They became very notorious in the computer world for their ongoing series of lawsuits and claims that they 'own' the
Linux operating system, and that it illegally contains their source code. All of which is rather
ironic considering that they were a respected
Linux company for almost a decade before they began these actions.