GNU/Linux is a free and open source software Unix-like operating system for computers. An operating system is a collection of the basic instructions that manage the electronic parts of the computer allowing running application programs. Linux is Free and open source software (FOSS). Free and open source software (FOSS) means that everyone has the freedom to use it, see how it works, change it or share it.
There is a lot of software for Linux and—like Linux itself—a lot of the software for Linux is free software. This means that it doesn't put any license restrictions on users. This is one reason why many people like to use Linux.
Some Popular Distributions: