Microsoft is the biggest enterprise software company in the world and one of the most profitable.

But it's flagship product, Windows, is the walking undead, thanks to Microsoft's two huge gaffs: missing out on mobile, and Windows 8, which turned Windows into something the typical consumer doesn't recognize.

By building its own Surface PCs and smartphones (with the purchase of Nokia's mobile phone unit), Microsoft has ditched the strategy that originally made Windows win the world. Instead of leaving the PC hardware to many partners, Microsoft wants it all. 

To no one's surprise, this isn't going over well so far. Sales of Surface PCs are lukewarm and one of Microsoft's biggest hardware partners, HP, is openly running to Google and calling Microsoft a competitor.

But Google didn't cause Microsoft's death spiral. Neither did Steve Jobs.

The credit goes to something called free open source software (FOSS) and an operating system called Linux, which came from a guy in his dorm room 22 years ago named Linus Torvalds.

FOSS is a vastly different way to write software. With FOSS, anyone can use the software for free, copy it, distribute it, change it, in some cases, even sell it (or sell services around it).

If there's a bug that needs fixing, or a feature that needs adding, users are free to do it themselves.

When software developers give their work away under an open source license, users will fix bugs and add new features the original programmer never even thought of. As the project grows in popularity, the developer makes money by offering support services. Red Hat has grown into a $1.3 billion company this way.

The Linux operating system (which in Linux-speak is called a "kernel") is proof that open source is an extremely efficient way of working and it's not the only example. There are lots of other open source projects like databases, storage software, networking software, Office software, and so on.

In fact, Android is a form of Linux.

Jim Zemlin


Jim Zemlin, Executive Director, Linux Foundation

Linux powers Google's massive data centers ... and Facebook's, Amazon's, Twitter's, every huge Internet operator. It's used by stock trading platforms like the New York Stock Exchange and London Stock ExchangeJim Zemlin, Executive Director of the Linux Foundation told Business Insider.

"The Linux kernel changes eight times an hour. There are 10,000 lines of code added a day, 8,000 lines of code subtracted. Even Amazon and Google couldn't keep up with that level of development on their own," Zemlin says.

Ingenious people have modified Linux to work on huge supercomputers, and on tiny devices, like the $25 Raspberry Pi PC. (Pi, in turn powers all kinds of other amazing inventions). Today, Linux runs everything from automobiles to televisions, Zemlin says. 

Plus, many of the developer tools used to write Linux are also open source. Torvalds invented Git, a tool for managing open source projects. That lead a few other guys, who had never even met Torvalds at the time, to use it for a company called GitHub, they told Business Insider. GitHub has since become the most popular place to store and share other open source projects.

Google, Twitter, Facebook and others have given away lots of open source developer tools, too.

This all adds up to a non-profit organization, the Linux Foundation, with a $25 million annual budget. The money, and engineering talent, comes from companies like HP, IBM, Oracle, Intel, Samsung, Google, Cisco and others, the Foundation says.

Microsoft spent a decade being an enemy of open source. Today Microsoft does offer lots of software via its own open source licenses, but not its biggest products like Windows, Windows Phone, Windows Server, SQL Server, etc.

Microsoft is still forced to keep up. Its execs have vowed to release new versions of all of its software every year, instead of its previous three-to-five year cycle

But it's on its own to build the software, fix the bugs, and so on. Meanwhile, a $25 million organization is producing 18,000 code changes a day and giving it all away for free.

Thanks to Linus Torvalds.