Linux: 75% paid effort
By Pulkit Sharma

The Linux operating system is one of the great success stories of the free and open source software movement.  It is the result of a universal, collaborative effort by mainly volunteers who are happy for others to use and enhance their labour of love.

When Richard Stallman launched the GNU Project in 1984 to create a free operating system, he was dismissed as an impractical idealist.  Today, he is revered as a visionary.  Richard Stallman and Linus Torvalds are seen as the fathers of the Linux operating system.

Linux had an uphill battle to be accepted in the commercial world.  Not surprisingly, software giants like Microsoft did everything they could to crush their ‘free’ competitor. Today, Linux had gained mainstream acceptance.

Even today, for most people Linux is a ‘free’ operating system developed by dedicated volunteers.  In reality, 75 percent of Linux code is being written by paid developers

APC is reporting

“
During a presentation at Linux.conf.au 2010 in Wellington, LWN.net founder and kernel contributor Jonathan Corbet offered an analysis of the code contributed to the Linux kernel between December 24 2008 and January 10 2010. (The kernel serves as a basis from which individual distributions such as Ubuntu, Debian or Red Hat are developed, though these will often add or remove specific features.)

The most striking aspect of the analysis (at the Linux Conf in Wellington), however, was where those lines of code originated from. 18% of contributions to the kernel were made without a specific corporate affiliation, suggesting true volunteer efforts. An additional 7% weren't classified. The remainder were from people working for specific companies in roles where developing that code was a major requirement. "75% of the code comes from people paid to do it," Corbet said.

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So, in a way, Linux has grown so mainstream that big business is paying developers to enhance this ‘free’ software for its use.