Linux, as it is said, is as much a phenomenon as it is an operating system.
To understand why Linux has become so popular and in order to understand Linux as an OS and as a philosophy, we need to know a little about another OS called Unix. Unix is a family of OSs that derive from the original AT&T Unix. Its development was started in the 1970s at the Bell Labs research center by Ken Thompson, Dennis Ritchie, and others. Initially intended for use inside the Bell System, AT&T licensed Unix to outside parties in the late 1970s, leading to a variety of both academic and commercial Unix variants from vendors.
MINIX was created by Andrew S. Tanenbaum, a computer science professor, and released in 1987 as a minimal Unix-like operating system targeted at students and others who wanted to learn the operating system principles. Although the complete source code of MINIX was freely available, the licensing terms prevented it from being free software.
On the other end of the spectrum, the GNU Project was started in 1983 by Richard Stallman. Stallman was a proponent of free-software and he had the goal of creating a “complete Unix-compatible software system” composed entirely of free software. Work on GNU began in 1984. Later, in 1985, Stallman started the Free Software Foundation and wrote the GNU General Public License (GNU GPL) in 1989. But by 1991 the implementation of GNU was still incomplete. Linus Torvalds has stated that if the GNU kernel had been available at the time (1991), he would not have decided to write his own.
Linux came up as an alternative to the proprietary UNIX and the restricted use MINIX Operating Systems and was first released on 17.09.1991 by Linus Torvalds
Linux is basically a kernel (refer to the post on Operating Systems to know more about kernels). There are various OSs which are based on Linux, and thus, Linux can be loosely referred to as a family of OSs based on the Linux kernel.
Various OSs based upon the Linux kernel are referred to as Distributions or simply Distros.
Linux is a Free and Open Source Software (FOSS), which means that anyone is free to use and modify it or build an OS upon it. Due to this very nature there are various Linux Distributions, all of them are different from one another in some aspects. Some of the popular distributions include Fedora, Ubuntu, Debian, Red Hat, etc.
Linux provides a lot of flexibility to the users and developers/programmers alike. There are some Linux distributions which are text-based (command-line) and then there are plenty of others which have a graphical interface. There are distributions which are better for performing a particular type of work – e.g. server handling, media playback and editing, general use, etc. For every kind of use, you can almost always find more than one distribution. Many users try various distros before settling upon a particular one.
As of 2015, over four hundred distributions are actively developed, with about a dozen distributions being most popular for general-purpose use. The Android OS for smartphones is a derivative of Linux. There are even versions of Linux that run on a minimal hardware and breathe new life into hardware which you might otherwise feel like throwing away.
For Wikipedia entry on Linux, click here.
For Wikipedia entry on Operating System, click here.
For more posts on Operating Systems, click here.
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