The big dirty secret is that Windows is based upon Unix!!! Microsoft's first product was Zenix a flavor of Unix albeit a bad and really really slow one. If you dig deep enough (and I have) all those Unix O/S calls are there. It is not a coincidence that 2 years after Cal Berkley thru Unix source code over the fence to the public domain Windows NT appeared. Originally laughable (ever tried to hook a modem up to NT 3?) at the time it is the undisputed king of the civilized world.
Any time someone is foolish enough to talk about Apple computers, I remind them they are toys, not work tools. When you can design a bridge for both stability, controls, and dynamics on a Mac, output the bill of materials and send design documents to the subcontractors that they can build and bill to. I will call it a tool. In the meantime it is a toy. So what are we left with? Not much really.
1) IBM Mainframe a very small niche
2) VxWorks (very very much Berkley BSD with an interrupt handler, and deterministic scheduler) and a bunch of other realtime O/S products that have market share like a Windows Phone (proof Microsoft makes mistakes)
3) Vaxes and Solaris boxes bought for next to nothing
4) my personal favorite the SGI beer cooler
You want students to be employable? Teach them Microsoft and Visual Studio and all the Microsoft business technology because the odds are they will email with Exchange, work on a Microsoft desktop, and store documents in SharePoint, plan products with Project, and store data in SQL Server and do big data/big data table in Hadoop with SQL Server extensions.
In 5 years Oracle will stop making Sun boxes that only zealots with government money buy. Oracle already loses money on their hardware each and every quarter; are you listening Larry?. When thinking about Oracle think of Data General, Silicon Graphics and Integraph. Java will continue its ossification and decay.
Facebook and Google use copious amounts of cheap Linux boxes. Linux is free because it really isn't much good. The world does not need Facebook which will be gone in 10 years and the rest of the world will realize Google is a front end and that the NSA has backend superuser access to everything Google does in spite of public denials.
Other than that Microsoft, in spite of all their mistakes, will continue to rule the world, except maybe cell phones, but no one needs a cell phone like they need food, clothing, shelter and a business desktop to do work.
Apple will eventually be $20/share again. Bill Gates is the richest man in the world because he deserves to be. Linus Torvalds doesn't matter. BSD Unix matters and Windows is a BSD box with a windowing system and development tool set that are richer than anything else in the computing world.
Feel free to denounce me as a fool, but I accurately predicted the demise of Digital Equipment, Integraph, SGI and Sun. A lot of shareholders would have done a whole lot better had they listened to me instead of, well almost everyone else. The price of Apple stock is a bubble, fundamentals aren't their, ask Ben Graham or Warren Buffet. Clip this paragraph of mine and 5 years from now you will realize how prescient I am and will have wished you sold your Apple stock. In the meantime I have to get back to work on Windows desktop.
I still have a place for Unix: I am looking for the perfect 1994 Silicon Graphics 'Predator' box for my bonus that I can turn into a beer cooler for the bonus room. Onyx boxes are too passé. VAX's makes nice end tables but have no visual panache like vintage SGI.
"Take that, you hostile sons-of-bitches!" -- James Coburn, in the finale of _The_President's_Analyst_