A Linux distribution is a member of the family of Unix-like operating systems built on top of the Unix-likeLinux kernel. Such distributions (often called distros for short) are Linux kernelOperating systems including a large collection of software applications such as word processors, spreadsheets, media players, and database applications. The Operating systemsoperating system will consist of the Linux kernel and, usually, a set of libraries and utilities from the operating systemGNU project, with X Window Systemgraphicsgraphics support from the X Window System. Distributions optimized for size may not contain X and tend to use more compact alternatives to the GNU utilities, such as Busybox, uClibc, or dietlibc. There are currently over six hundred Linux distributions. Over three hundred of those are in active development, constantly being revised and improved.
Because most of the kernel and supporting packages are X Window Systemfree and open source softwarefree and open source software, Linux distributions have taken a wide variety of forms — from fully featured desktop, server, laptop, netbook, Mobile Phone, and Tablet operating systems as well as minimal environments (typically for use in free and open source softwareembedded systemsembedded systems or for booting from a floppy disk). Aside from certain custom software (such as installers and configuration tools), a distribution is most simply described as a particular assortment of applications installed on top of a set of libraries married with a version of the kernel, such that its “out-of-the-box” capabilities meet most of the needs of its particular end-user base.
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