Definition - What does Linux mean?
Linux is a free open source operating system (OS) based on UNIX that was created in 1991 by Linus Torvalds. Users can modify and create variations of the source code, known as distributions, for computers and other devices. The most common use is as a server, but Linux is also used in desktop computers, smartphones, e-book readers and gaming consoles, etc.
A distribution of Linux includes the kernel (the central OS component and the bridge between a software application and its data), system utilities, programs and tools for downloading, installing and uninstalling OS updates.
Techopedia explains Linux
Distributed worldwide under a General Public License (GNU), meaning "GNUs not UNIX" (a recursive acronym), there are literally hundreds of Linux distributions or "distros" around the world. Many desktop Linux distributions have intuitive graphical user interfaces (GUI), which allow greater ease of use than their predecessors. Objects and data are easily manipulated and have resizable icons, windows, buttons, folders and other features similar to Windows.
Proponents consider Linux a robust, scalable and flexible OS. It is suited to programming, and many companies use Linux as a development platform. Critics point to the lack of application support and user friendliness. Similar to the PC/Mac debate, the Linux/Windows comparison is often a heated discussion with no easy answers, due to the inherent subjectivity.