Qdos was the name of the OS - more a monitor than a OS - that Bill Gates bought from Tim Paterson. Since Tim wasn't able to market his system and had no further use for QDOS, he offered Bill Gates his OS for little money. Bill Gates bought it for less money. In a happy coincidence of events IBM knocked at this time on Billys door, asking if he couldn't sell them an OS for a new PC they wanted to bring on the market. This was the birth of MSDOS.

QNX
A micro-kernel, distributed, real-time, fault-tolerant, POSIX-certified OS for the x86. QNX adopts the approach of implementing an OS with a 10 Kbyte micro-kernel surrounded by a team of optional processes that provide higher-level OS services. QNX is fully distributed, with all system interfaces network transparent. QNX has successfully been used in tiny ROM-based embedded systems and in several-hundred node distributed systems.

OpenQNX: The QNX community portal
http://www.openqnx.com is one of the most popular QNX community
website. News, explanations, FAQ, forums, newsgroups, mailing lists, software
downloads, weblinks, tech reviews, searches, fun, tips, online live
support. Created as the central information resource (English) for the QNX
community.

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