
1) Red Hat alternative
Found on
https://www.crosswordclues.com/clue/windows-nt

A version of MS Windows that provides Task Switching and no application memory protection layered over a multitasking, protected OS.
Found on
http://www.encyclo.co.uk/local/20091

Microsoft Windows operating system based on a full 32 bit GDI and applications interface. It includes high levels of security and protection of the operating systems from application errors. Supports most 16 bit applications, but many DOS application requiring direct access to the hardware will not work
Found on
http://www.vutrax.co.uk/glossary.htm
No exact match found.