Linux
GNU/Linux systems are used in every domain, from smartphones with Android to supercomputers, and most certainly in servers deployment. Use of Linux desktops in home and enterprise desktops has been steadily growing.
As a server, Linux is mostly used for web, file and database servers. It is a perfect choice OS for small businesses who use a file server to store their data in a central location.
Advantages
Cost: The most obvious advantage of using Linux is the fact that it is free to obtain; there is no need to spend time and money to purchase licenses since Linux comes with the GNU General Public License. Additionally, there are large repositories from which you can freely download high quality software for almost any task you can think of.
Stability: Linux doesn’t need to be rebooted periodically to maintain performance levels. It doesn’t freeze up or slow down over time due to memory leaks and such. Continuous up-times of hundreds of days, even years are not uncommon.
Performance: Linux runs on almost any hardware new and old. It provides continuous high performance. It can handle unusually large numbers of users simultaneously.
Security: Linux is one of the most secure operating systems. The Linux operating system has been around since the early nineties and has managed to stay secure despite the widespread and ever increasing number of viruses, spyware and adware for all these years.