QuoteNeXTSTEP is a Unix operating system developed in the 1980s and 90s by NeXT, based on a Mach microkernel with an advanced graphical user interface. NeXTSTEP supports several 32-bit HP 9000 PA-RISC workstations in release 3.3 from 1994, for which HP and NeXT had high hopes. This was an effort to open up the NeXT operating system to other hardware platforms after NeXT stopped designing its own custom NeXT computers.