Linux or GNU/Linux is a Unix-likeoperating system (or strictly family of) 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 software, meaning 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 is one reason why many people like to use Linux.
Linux was originally developed for personal computers. Linux is the leading operating system on servers such as mainframe computers, and the only OS used on supercomputers (at least on the TOP500 list, since November 2017). It is used by around 2.3 percent of desktop computers. The Chromebook, which runs the Linux kernel-based Chrome OS, dominates the US K–12 education market and represents nearly 20 percent of sub-$300 notebook sales in the US.
Linux is one of the most prominent examples of free and open-source software collaboration. The source code may be used, modified and distributed—commercially or non-commercially—by anyone under the terms of its respective licenses, such as the GNU General Public License.
In the 1980s, many people liked to use an operating system called Unix. But because it restricted the user from sharing and improving the system, some people made a new operating system that would work like Unix but which anybody could share or improve. MINIX, similar to Unix, was used as a teaching tool for university students to learn how operating systems worked. MINIX also restricted its sharing and improvement by its users.
A group of people called the GNU Project wrote different parts of a new operating system called GNU, but it did not have all the parts an operating system needs to work. In 1991 Linus Torvalds began to work on a replacement for MINIX that would be free to use, and which would not cost anything. Linus started the project when he was attending the
University of Helsinki. This eventually became the Linux kernel.
Linus Torvalds shared the Linux kernel on some internet groups for MINIX users. Linus first called the operating system "Freax". The name Freax came from joining up the English words "free" and "freak", and adding an X to the name because Unix has an X in its name. Ari Lemmke, who worked with Linus at the University, was responsible for the servers that Freax was stored on. Ari did not think Freax was a good name, so he called the project "Linux" without asking Linus. Later, Linus agreed that Linux was a better name for his project.
Linux relied on software code from MINIX at first. But, with code from the GNU system available for free, he decided it would be good for Linux if it could use that code, instead of code from MINIX, because MINIX did not let people share or change it how they wanted. The GNU General Public License is a software license that lets people change any part of the code they want to, as long as they share any changes they make with the people they give their software to and allow them to redistribute it for free or for a price . The software from GNU was all licensed under the GNU General Public License, so Linus and the other people who worked on Linux could use it too.
To make the Linux kernel suitable for use with the code from the GNU Project, Linus Torvalds started a switch from his original license (which did not allow people to sell it) to the GNU GPL. Linux and GNU developers worked together to integrate GNU code with Linux to make a free operating system.