Who writes and contributes to Linux code?

,----[ Quote ]
| There are several explanations for this, McPherson said. One is that more
| vendors want to put code for their products into the Linux kernel, so they
| are putting people on the job to make such contributions for their products.
| Also possible, she said, are steady increases in server market share for
| Linux and the increasing embedded use of the operating system, leading to
| greater contributions from related companies.


Linux Foundation: Paid Contributors Helping to Grow Kernel

,----[ Quote ]
| Linux is being used more often as the firmware found in consumer electronics,
| and now more than 70 percent of all kernel development is done by paid
| professionals.



NEWS: Linux Developers Make A Living

,----[ Quote ]
| Yes, I said paid professionals.
| [...]
| McPherson also notes that “it’s difficult for most people to get their minds
| around competitive mass collaboration.” Indeed, this is what the freedom
| afforded by Linux is all about. People (and companies) contribute not for
| humanitarian reasons, but because they expect a benefit. Work together to
| create the best platform, openly usable by everyone, and if it still doesn’t
| meet your needs perfectly, you are free to change it accordingly. Everyone
| wins. No compromises. * * *


Linux kernel developers have tripled in number

,----[ Quote ]
| The Linux Foundation (LF) has published a study on Linux mainline kernel
| development. According to LF, the number of Linux kernel developers has
| tripled since 2005, with many more companies contributing to the process
| (including, potentially, the latest new LF member, Adobe). *



Linux Will Be Worth $1 Billion In First 100 Days of 2009

,----[ Quote ]
| The kernel development process is adding 2,000 lines of code a day or roughly
| another 160,000 by the end of 2007. By the end of 2008, it will have added
| another 730,000. So the kernel will have close to 6.4 millions lines of code,
| using Wheeler's methodology, at the end of next year. Sometime during the
| first 100 days of 2009, Linux will cross the 6.6 million lines of code mark
| and $1 billion in value. * *