GitGit (gɪt) is a distributed version control system that tracks changes in any set of s, usually used for coordinating work among programmers who are collaboratively developing source code during software development. Its goals include speed, data integrity, and support for distributed, non-linear workflows (thousands of parallel branches running on different computers). Git was originally authored by Linus Torvalds in 2005 for development of the Linux kernel, with other kernel developers contributing to its initial development.
Comparison of version-control softwareIn software development, version control is a class of systems responsible for managing changes to computer programs or other collections of information such that revisions have a logical and consistent organization. The following tables include general and technical information on notable version control and software configuration management (SCM) software. For SCM software not suitable for source code, see Comparison of open-source configuration management software.
Version controlIn software engineering, version control (also known as revision control, source control, or source code management) is a class of systems responsible for managing changes to computer programs, documents, large web sites, or other collections of information. Version control is a component of software configuration management. Changes are usually identified by a number or letter code, termed the "revision number", "revision level", or simply "revision". For example, an initial set of files is "revision 1".
Distributed version controlIn software development, distributed version control (also known as distributed revision 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 (except pushing and pulling), improves the ability to work offline, and does not rely on a single location for backups.
Branching (version control)Branching, in version control and software configuration management, is the duplication of an object under version control (such as a source code file or a directory tree). Each object can thereafter be modified separately and in parallel so that the objects become different. In this context the objects are called branches. The users of the version control system can branch any branch. Branches are also known as trees, streams or codelines.
Repository (version control)In version control systems, a repository is a data structure that stores metadata for a set of files or directory structure. Depending on whether the version control system in use is distributed, like Git or Mercurial, or centralized, like Subversion, CVS, or Perforce, the whole set of information in the repository may be duplicated on every user's system or may be maintained on a single server. Some of the metadata that a repository contains includes, among other things, a historical record of changes in the repository, a set of commit objects, and a set of references to commit objects, called heads.
GitHubGitHub, Inc. (ˈgɪthʌb) is a platform and cloud-based service for software development and version control using Git, allowing developers to store and manage their code. It provides the distributed version control of Git plus access control, bug tracking, software feature requests, task management, continuous integration, and wikis for every project. Headquartered in California, it has been a subsidiary of Microsoft since 2018. It is commonly used to host open source software development projects.
Concurrent Versions SystemConcurrent Versions System (CVS, also known as the Concurrent Versioning System) is a revision control system originally developed by Dick Grune in July 1986. CVS operates as a front end to RCS, an earlier system which operates on single files. It expands upon RCS by adding support for repository-level change tracking, and a client-server model. Released under the terms of the GNU General Public License, CVS is free software. CVS operates as a front end to Revision Control System (RCS), an older version control system that manages individual files but not whole projects.
Atomic commitIn the field of computer science, an atomic commit is an operation that applies a set of distinct changes as a single operation. If the changes are applied, then the atomic commit is said to have succeeded. If there is a failure before the atomic commit can be completed, then all of the changes completed in the atomic commit are reversed. This ensures that the system is always left in a consistent state. The other key property of isolation comes from their nature as atomic operations.
Two-phase commit protocolIn transaction processing, databases, and computer networking, the two-phase commit protocol (2PC, tupac) is a type of atomic commitment protocol (ACP). It is a distributed algorithm that coordinates all the processes that participate in a distributed atomic transaction on whether to commit or abort (roll back) the transaction. This protocol (a specialised type of consensus protocol) achieves its goal even in many cases of temporary system failure (involving either process, network node, communication, etc.
Three-phase commit protocolIn computer networking and databases, the three-phase commit protocol (3PC) is a distributed algorithm which lets all nodes in a distributed system agree to commit a transaction. It is a more failure-resilient refinement of the two-phase commit protocol (2PC). A two-phase commit protocol cannot dependably recover from a failure of both the coordinator and a cohort member during the Commit phase. If only the coordinator had failed, and no cohort members had received a commit message, it could safely be inferred that no commit had happened.
Commitment orderingCommitment ordering (CO) is a class of interoperable serializability techniques in concurrency control of databases, transaction processing, and related applications. It allows optimistic (non-blocking) implementations. With the proliferation of multi-core processors, CO has also been increasingly utilized in concurrent programming, transactional memory, and software transactional memory (STM) to achieve serializability optimistically. CO is also the name of the resulting transaction schedule (history) property, defined in 1988 with the name dynamic atomicity.
Web browserA web browser is an application for accessing websites. When a user requests a web page from a particular website, the browser retrieves its from a web server and then displays the page on the user's screen. Browsers are used on a range of devices, including desktops, laptops, tablets, and smartphones. In 2020, an estimated 4.9 billion people have used a browser. The most used browser is Google Chrome, with a 65% global market share on all devices, followed by Safari with 18%.
Mozilla CorporationThe Mozilla Corporation (stylized as moz://a) is a wholly owned subsidiary of the Mozilla Foundation that coordinates and integrates the development of Internet-related applications such as the Firefox web browser, by a global community of open-source developers, some of whom are employed by the corporation itself. The corporation also distributes and promotes these products. Unlike the non-profit Mozilla Foundation, and the Mozilla open source project, founded by the now defunct Netscape Communications Corporation, the Mozilla Corporation is a taxable entity.
FirefoxMozilla Firefox, or simply Firefox, is a free and open-source web browser developed by the Mozilla Foundation and its subsidiary, the Mozilla Corporation. It uses the Gecko rendering engine to display web pages, which implements current and anticipated web standards. In November 2017, Firefox began incorporating new technology under the code name "Quantum" to promote parallelism and a more intuitive user interface. Firefox is available for Windows 7 or later versions, macOS, and Linux.
MozillaMozilla (stylized as moz://a) is a free software community founded in 1998 by members of Netscape. The Mozilla community uses, develops, publishes and supports Mozilla products, thereby promoting exclusively free software and open standards, with only minor exceptions. The community is supported institutionally by the non-profit Mozilla Foundation and its tax-paying subsidiary, the Mozilla Corporation.
Firefox version historyFirefox was created by Dave Hyatt and Blake Ross as an experimental branch of the Mozilla browser, first released as Firefox 1.0 on November 9, 2004. Starting with version 5.0, a rapid release cycle was put into effect, resulting in a new major version release every six weeks. This was gradually accelerated further in late 2019, so that new major releases occur on four-week cycles starting in 2020. Firefox early version history In March 2011, Mozilla presented plans to switch to a faster 16-week development cycle, similar to Google Chrome.
Mozilla FoundationThe Mozilla Foundation (stylized as moz://a) is an American non-profit organization that exists to support and collectively lead the open source Mozilla project. Founded in July 2003, the organization sets the policies that govern development, operates key infrastructure and controls Mozilla trademarks and copyrights. It owns two taxable subsidiaries: the Mozilla Corporation, which employs many Mozilla developers and coordinates releases of the Mozilla Firefox web browser, and MZLA Technologies Corporation, which employs developers to work on the Mozilla Thunderbird email client and coordinate its releases.
Mozilla ThunderbirdMozilla Thunderbird is a free and open-source cross-platform email client, personal information manager, news client, RSS and chat client that is operated by the Mozilla Foundation's subsidiary MZLA Technologies Corporation. Thunderbird is an independent, community-driven project that is managed and overseen by the Thunderbird Council, which is elected by the Thunderbird Community. The project strategy was originally modeled after that of Mozilla's Firefox web browser and is an interface built on top of that web browser.
Apache SubversionApache Subversion (often abbreviated SVN, after its command name svn) is a software versioning and revision control system distributed as open source under the Apache License. Software developers use Subversion to maintain current and historical versions of files such as source code, web pages, and documentation. Its goal is to be a mostly compatible successor to the widely used Concurrent Versions System (CVS). The open source community has used Subversion widely: for example, in projects such as Apache Software Foundation, FreeBSD, SourceForge, and from 2006 to 2019, GCC.
