Linux is the most powerful and popular OS in the world. It is a open source source software. The code used to create linux is free and also available to view, edit and especially for the users who have appropriate skills can contribute to it. It is widely used in the IT industry these days. It provides better security with respect to other OS in the market. Linux runs on most of the devices in the world. The chances of getting virus in the linux OS is very less as compared to other OS such as Windows or MAC.
There are many distributions of linux in the market but the common thing between them is the core linux codes are generally common. The varies distribution of linux gives different softwares with it, as per the user requirement it chooses the distribution.
How Linux is different from Unix ?
Unix OS is developed in 1970s ate Bell Labs by Ken Thompson, Dennis Ritchie, and others. Both have similar tools for interfacing with system. Linux was created to be similar to Unix. Both also have similar file system layouts and other key components.
But the major difference between two is that unix is not free. There are several attempts to create a Os which is likely Unix or Unix compatible but linux has the most successful OS in popularity.
Lists of some Linux based OS:-
1) Linus Mint