Free software, libre software, or libreware is computer software distributed under terms that allow users to run the software for any purpose as well as to study, change, and distribute it and any adapted versions. Free software is a matter of liberty, not price; all users are legally free to do what they want with their copies of a free software regardless of how much is paid to obtain the program. Computer programs are deemed "free" if they give end-users ultimate control over the software and, subsequently, over their devices.
GNU is an extensive collection of free software, which can be used as an operating system or can be used in parts with other operating systems. The use of the completed GNU tools led to the family of operating systems popularly known as Linux. Most of GNU is licensed under the GNU Project's own General Public License (GPL).
A Linux distribution is an operating system made from a software collection that includes the Linux kernel and often a package management system. Linux users usually obtain their operating system by downloading one of the Linux distributions, which are available for a wide variety of systems ranging from embedded devices and personal computers to powerful supercomputers.
Darwin is the core Unix operating system of macOS, iOS, watchOS, tvOS, iPadOS, visionOS, and bridgeOS. It previously existed as an independent open-source operating system, first released by Apple Inc. in 2000. It is composed of code derived from NeXTSTEP, FreeBSD, other BSD operating systems, Mach, and other free software projects' code, as well as code developed by Apple.
Source Mage is a source-based Linux distribution descended from Sorcerer. Components of this operating system are downloaded as source code and compiled locally on the user's computer.
The GNU Project is a free software, mass collaboration project announced by Richard Stallman on September 27, 1983. Its goal is to give computer users freedom and control in their use of their computers and computing devices by collaboratively developing and publishing software that gives everyone the rights to freely run the software, copy and distribute it, study it, and modify it. GNU software grants these rights in its license.
Portage is a package management system originally created for and used by Gentoo Linux and also by ChromeOS, Calculate, Sabayon, and Funtoo Linux among others. Portage is based on the concept of ports collections. Gentoo is sometimes referred to as a meta-distribution due to the extreme flexibility of Portage, which makes it operating-system-independent. The Gentoo/Alt project was concerned with using Portage to manage other operating systems, such as BSDs, macOS and Solaris. The most notable of these implementations is the Gentoo/FreeBSD project.
A patch is a set of changes to a computer program or its supporting data designed to update or repair it. This includes bugfixes or bug fixes to remove security vulnerabilities and correct bugs (errors). Patches are often written to improve the functionality, usability, or performance of a program. The majority of patches are provided by software vendors for operating system and application updates.
Ingo Molnár, employed by Red Hat as of May 2013, is a Hungarian Linux hacker. He is known for his contributions to the operating system in terms of security and performance.
udev is a device manager for the Linux kernel. As the successor of devfsd and hotplug, udev primarily manages device nodes in the /dev directory. At the same time, udev also handles all user space events raised when hardware devices are added into the system or removed from it, including firmware loading as required by certain devices.
In software development, distributed version control is a form of version control in which the complete codebase, including its full history, is mirrored on every developer's computer. Compared to centralized version control, this enables automatic management branching and merging, speeds up most operations, improves the ability to work offline, and does not rely on a single location for backups. Git, the world's most popular version control system, is a distributed version control system.
A free and open-source graphics device driver is a software stack which controls computer-graphics hardware and supports graphics-rendering application programming interfaces (APIs) and is released under a free and open-source software license. Graphics device drivers are written for specific hardware to work within a specific operating system kernel and to support a range of APIs used by applications to access the graphics hardware. They may also control output to the display if the display driver is part of the graphics hardware. Most free and open-source graphics device drivers are developed by the Mesa project. The driver is made up of a compiler, a rendering API, and software which manages access to the graphics hardware.
Squashfs is a compressed read-only file system for Linux. Squashfs compresses files, inodes and directories, and supports block sizes from 4 KiB up to 1 MiB for greater compression. Several compression algorithms are supported. Squashfs is also the name of free software, licensed under the GPL, for accessing Squashfs filesystems.
In the context of free and open-source software, proprietary software only available as a binary executable is referred to as a blob or binary blob. The term usually refers to a device driver module loaded into the kernel of an open-source operating system, and is sometimes also applied to code running outside the kernel, such as system firmware images, microcode updates, or userland programs. The term blob was first used in database management systems to describe a collection of binary data stored as a single entity.
FreeBSD is a free and open-source Unix-like operating system descended from the Berkeley Software Distribution (BSD). The first version of FreeBSD was released in 1993 developed from 386BSD and the current version runs on x86, ARM, PowerPC and RISC-V processors. The project is supported and promoted by the FreeBSD Foundation.
Quilt is a software utility for managing a series of changes to the source code of any computer program. Such changes are often referred to as "patches" or "patch sets". Quilt can take an arbitrary number of patches as input and condense them into a single patch. In doing so, Quilt makes it easier for many programmers to test and evaluate the different changes amongst patches before they are permanently applied to the source code.
The Linux kernel is a free and open-source, monolithic, modular, multitasking, Unix-like operating system kernel. It was originally written in 1991 by Linus Torvalds for his i386-based PC, and it was soon adopted as the kernel for the GNU operating system, which was written to be a free (libre) replacement for Unix.
According to the Free Software Foundation Latin America, Linux-libre is a modified version of the Linux kernel that contains no binary blobs, obfuscated code, or code released under proprietary licenses. In the Linux kernel, they are mostly used for proprietary firmware images. While generally redistributable, binary blobs do not give the user the freedom to audit, modify, or, consequently, redistribute their modified versions. The GNU Project keeps Linux-libre in synchronization with the mainline Linux kernel.
NetBSD is a free and open-source Unix operating system based on the Berkeley Software Distribution (BSD). It was the first open-source BSD descendant officially released after 386BSD was forked. It continues to be actively developed and is available for many platforms, including servers, desktops, handheld devices, and embedded systems.
Sage Sharp is an American software engineer who has worked on the Linux kernel, including serving on the Linux Foundation's Technical Advisory Board for two years.
