Linux is a free and open sourced operating system based on the kernel (core operating system features) created by Linus Torvalds and maintained by he and a host of others around the world. Linux is an alternative to Windows and Mac OS both as a true option for using a computer and in that it is not a closed source operating system as the others are. This means that you can modify the code and make it look and work how you wish so long as you attribute the source of the code changed. While versions (distributions) are centrally distributed for use what you do with the distribution is not, so your data is yours (that which you do not provide other organizations such as Google, Facebook, etc.) and is not collected and stored by another.