Why do We Choose Linux?

Linux, named after the inventor, Linus Torvalds, is a so different OS for everyone against Windows. To everyone who used to use Windows, Linux need us to do more for everything which we usually do by computer, such as playing a video.
Someone says, Linux is for the ones who are good at the computer technique. For example the programmer use Linux to program, or the mathematician use it to do the numerical work.. It’s right. Linux always used by the professional formerly, because this OS ask the operator knows a lot about the OS how to work. Compared to Linux, Windows seems very easy for us, and in the most time, clicking the mouse is enough.
But there are two problems for us. The first one is did we get all the licenses for the software we are using. I think there is almost no one can say ‘Yes, I did’ in China, who use Windows. In the daily life, we used the piracy of the OS and the application software, although we know is wrong. There a fact that we can’t afford Windows. The price of a license for Windows XP is of equal value to a new computer without OS. So we can only choose the piracy. But Linux is free for everyone. It means you pay nothing for The OS to use it. What you do is only downloading the image from Internet and installing it. And if you are good at programming, you can rebuild the OS for yourself. It’s amazing that you can make your OS to be personality, different from all the others.
The second one is why we give up the right to know how the OS manage our computers. We paid for the computer’s CPU, mainboard, and hard disk, even the OS, but we don’t know they are how to work. I think it isn’t fair for everyone. Someone says, I don’t interest in how the computer work, but he must be interest in how to make the computer start work which is shutdown, in only 10 seconds. If you know how the computer work and optimize the process, you can do it by Linux. Of cause if you want to know what all the part