Linux, according to wikipedia, is a generic term that commonly refers to Unix-like computer operating systems that use the Linux kernel. Linux is one of the most prominent examples of free software and open source development; typically all the underlying source code can be used, freely modified, and redistributed by anyone.
Linux is predominantly known for its use in servers, although it is installed on a wide variety of computer hardware, ranging from embedded devices and mobile phones to supercomputers, and its popularity as a desktop/laptop operating system is growing due to the rise of netbooks and the Ubuntu distribution of the operating system.
In the chapter, The Cathedral and the Bazaar, linux is said to be subversive. It is a world class operating system. All the hackers in the world are been united by the internet.
At first, I can’t see any connection with Linux and the title of the chapter. But as I read the contents of this chapter, it explains why it was named the cathedral and the bazaar. The cathedral is done in a crafty and careful way, so as the operating system, linux. It is compared to a bazaar because the way different things are marketed to it just to be perfect.
The author of the book tries to explain what linux and open source environment is all about.