What is GitHub

GitHub, Inc. is a provider of Internet hosting {1} for software development {2} and version control {3} using Git {4}. It offers the distributed version control {5} and source code management (SCM) {3} functionality of Git, plus its own features. It provides access control {6} and several collaboration features such as bug tracking {7}, feature requests {8}, task management {9}, continuous integration {10} and wikis {11} for every project. 

Headquartered in California, it has been a subsidiary of Microsoft since 2018.

GitHub offers its basic services free of charge. Its more advanced professional and enterprise services are commercial. Free GitHub accounts are commonly used to host open-source {12} projects. 

2019: As of January 2019, GitHub offers unlimited private repositories {13} to all plans, including free accounts, but allowed only up to three collaborators per repository for free.

2020: Starting from April 15, 2020, the free plan allows unlimited collaborators, but restricts private repositories to 2,000 minutes of GitHub Actions {14} per month.

As of January 2020, GitHub reports having over 40 million users and more than 190 million repositories (including at least 28 million public repositories), making it the largest host of source code {15} in the world.

Wikipedia Card

Type of business:  Subsidiary

Type of site:  Collaborative version control

Available in:  English

Founded:  February 8, 2008; 13 years ago (as Logical Awesome LLC)

Headquarters:  San Francisco, California, United States

Area served:  Worldwide

Founder(s):  
#1 Tom Preston-Werner
#2 Chris Wanstrath
#3 P. J. Hyett
#4 Scott Chacon

Key people:  
CEO:  Nat Friedman
CFO:  Mike Taylor 

Industry:  
#1 Collaborative version control (GitHub)
#2 Blog host (GitHub Pages)
#3 Package repository (NPM)

Revenue:  Increase $300 million (2018)

Employees:  1677

Parent:  Microsoft

URL:  github.com 

Registration:  Optional (required for creating and joining repositories)

Users:  56 million (as of September 2020)

Launched:  April 10, 2008; 13 years ago
Current status:  Active
Written in:  
#1 Ruby
#2 ECMAScript
#3 Go
#4 C 

Git-SCM
Git is a free and open source distributed version control system designed to handle everything from small to very large projects with speed and efficiency.

Git is easy to learn and has a tiny footprint with lightning fast performance. It outclasses SCM tools like Subversion, CVS, Perforce, and ClearCase with features like cheap local branching, convenient staging areas, and multiple workflows.

Ref: git-scm

Keywords

1. Internet hosting

An Internet hosting service is a service that runs servers connected to the Internet, allowing organizations and individuals to serve content or host services connected to the Internet.

A common kind of hosting is web hosting. Most hosting providers offer a combination of services - e-mail hosting, website hosting, and database hosting, for example. DNS hosting service, another type of service usually provided by hosting providers, is often bundled with domain name registration.

Dedicated server hosts, provide a server, usually housed in a datacenter and connected to the Internet where clients can run anything they want (including web servers and other servers). The hosting provider ensures that the servers have Internet connections with good upstream bandwidth and reliable power sources.

Another popular kind of hosting service is shared hosting. This is a type of web hosting service, where the hosting provider provisions hosting services for multiple clients on one physical server and shares the resources between the clients. Virtualization is key to making this work effectively.

Internet hosting

2. Software Development

Software development is the process of conceiving, specifying, designing, programming, documenting, testing, and bug fixing involved in creating and maintaining applications, frameworks, or other software components. Software development is a process of writing and maintaining the source code, but in a broader sense, it includes all that is involved between the conception of the desired software through to the final manifestation of the software, sometimes in a planned and structured process. Therefore, software development may include research, new development, prototyping, modification, reuse, re-engineering, maintenance, or any other activities that result in software products.

The software can be developed for a variety of purposes, the three most common being to meet specific needs of a specific client/business (the case with custom software), to meet a perceived need of some set of potential users (the case with commercial and open source software), or for personal use (e.g. a scientist may write software to automate a mundane task). Embedded software development, that is, the development of embedded software, such as used for controlling consumer products, requires the development process to be integrated with the development of the controlled physical product. System software underlies applications and the programming process itself, and is often developed separately.

The need for better quality control of the software development process has given rise to the discipline of software engineering, which aims to apply the systematic approach exemplified in the engineering paradigm to the process of software development.

There are many approaches to software project management, known as software development life cycle models, methodologies, processes, or models. The waterfall model is a traditional version, contrasted with the more recent innovation of agile software development.

Software development

3. Version control

In 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". When the first change is made, the resulting set is "revision 2", and so on. Each revision is associated with a timestamp and the person making the change. Revisions can be compared, restored, and with some types of files, merged.

The need for a logical way to organize and control revisions has existed for almost as long as writing has existed, but revision control became much more important, and complicated, when the era of computing began. The numbering of book editions and of specification revisions are examples that date back to the print-only era. Today, the most capable (as well as complex) revision control systems are those used in software development, where a team of people may concurrently make changes to the same files.

Version control systems (VCS) are most commonly run as stand-alone applications, but revision control is also embedded in various types of software such as word processors and spreadsheets, collaborative web docs[2] and in various content management systems, e.g., Wikipedia's page history. Revision control allows for the ability to revert a document to a previous revision, which is critical for allowing editors to track each other's edits, correct mistakes, and defend against vandalism and spamming in wikis.

Version control

4. Git

Git (/ɡɪt/) is software for tracking changes in any set of files, usually used for coordinating work among programmers 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 systems).

Git was created by Linus Torvalds in 2005 for development of the Linux kernel, with other kernel developers contributing to its initial development. Since 2005, Junio Hamano has been the core maintainer. As with most other distributed version control systems, and unlike most client–server systems, every Git directory on every computer is a full-fledged repository with complete history and full version-tracking abilities, independent of network access or a central server. Git is free and open-source software distributed under GNU General Public License Version 2.

Git

5. Distributed version control

In 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. Git, the world's most popular version control system, is a distributed version control system.

In 2010, software development author Joel Spolsky described distributed version control systems as "possibly the biggest advance in software development technology in the past ten years".

Distributed version control

6. Access control

In the fields of physical security and information security, access control (AC) is the selective restriction of access to a place or other resource while access management describes the process. The act of accessing may mean consuming, entering, or using. Permission to access a resource is called authorization.

Locks and login credentials are two analogous mechanisms of access control.

Access control

7. Bug tracking system

A bug tracking system or defect tracking system is a software application that keeps track of reported software bugs in software development projects. It may be regarded as a type of issue tracking system.

Many bug tracking systems, such as those used by most open-source software projects, allow end-users to enter bug reports directly. Other systems are used only internally in a company or organization doing software development. Typically bug tracking systems are integrated with other project management software.

A bug tracking system is usually a necessary component of a professional software development infrastructure, and consistent use of a bug or issue tracking system is considered one of the "hallmarks of a good software team".

Bug tracking system

8. Software feature

In software, a feature has several definitions. The Institute of Electrical and Electronics Engineers defines the term feature in IEEE 829 as "A distinguishing characteristic of a software item (e.g., performance, portability, or functionality)."

Software feature

9. Task management

Task management is the process of managing a task through its life cycle. It involves planning, testing, tracking, and reporting. Task management can help either individual achieve goals, or groups of individuals collaborate and share knowledge for the accomplishment of collective goals. Tasks are also differentiated by complexity, from low to high.

Effective task management requires managing all aspects of a task, including its status, priority, time, human and financial resources assignments, recurrence, dependency, notifications and so on. These can be lumped together broadly into the basic activities of task management.

Managing multiple individuals or team tasks may be assisted by specialized software, for example workflow or project management software.

Task management may form part of project management and process management and can serve as the foundation for efficient workflow in an organization. Project managers adhering to task-oriented management have a detailed and up-to-date project schedule, and are usually good at directing team members and moving the project forward.

Task management

10. Continuous integration

In software engineering, continuous integration (CI) is the practice of merging all developers' working copies to a shared mainline several times a day. Grady Booch first proposed the term CI in his 1991 method, although he did not advocate integrating several times a day. Extreme programming (XP) adopted the concept of CI and did advocate integrating more than once per day – perhaps as many as tens of times per day.

Continuous integration

11. Wiki

A wiki (/ˈwɪki/ WIK-ee) is a hypertext publication collaboratively edited and managed by its own audience directly using a web browser. A typical wiki contains multiple pages for the subjects or scope of the project and could be either open to the public or limited to use within an organization for maintaining its internal knowledge base.

Wikis are enabled by wiki software, otherwise known as wiki engines. A wiki engine, being a form of a content management system, differs from other web-based systems such as blog software, in that the content is created without any defined owner or leader, and wikis have little inherent structure, allowing structure to emerge according to the needs of the users. Wiki engines usually allow content to be written using a simplified markup language and sometimes edited with the help of a rich-text editor. There are dozens of different wiki engines in use, both standalone and part of other software, such as bug tracking systems. Some wiki engines are open source, whereas others are proprietary. Some permit control over different functions (levels of access); for example, editing rights may permit changing, adding, or removing material. Others may permit access without enforcing access control. Other rules may be imposed to organize content.

The online encyclopedia project, Wikipedia, is the most popular wiki-based website, and is one of the most widely viewed sites in the world, having been ranked in the top twenty since 2007. Wikipedia is not a single wiki but rather a collection of hundreds of wikis, with each one pertaining to a specific language. In addition to Wikipedia, there are hundreds of thousands of other wikis in use, both public and private, including wikis functioning as knowledge management resources, notetaking tools, community websites, and intranets. The English-language Wikipedia has the largest collection of articles: as of February 2020, it has over 6 million articles. Ward Cunningham, the developer of the first wiki software, WikiWikiWeb, originally described wiki as "the simplest online database that could possibly work." "Wiki"  is a Hawaiian word meaning "quick."

Wiki

12. Open source

Open source is source code that is made freely available for possible modification and redistribution. Products include permission to use the source code, design documents, or content of the product. It most commonly refers to the open-source model, in which open-source software or other products are released under an open-source license as part of the open-source-software movement. Use of the term originated with software, but has expanded beyond the software sector to cover other open content and forms of open collaboration.

Open source

13. Repository (version control)

In revision 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:

13.1. A historical record of changes in the repository.
13.2. A set of commit objects.
13.3. A set of references to commit objects, called heads.

Repository (version control)

14. GitHub Actions

Automate your workflow from idea to production.
GitHub Actions makes it easy to automate all your software workflows, now with world-class CI/CD. Build, test, and deploy your code right from GitHub. Make code reviews, branch management, and issue triaging work the way you want.

Ref 15.1: GitHub Actions

Automate, customize, and execute your software development workflows right in your repository with GitHub Actions. You can discover, create, and share actions to perform any job you'd like, including CI/CD, and combine actions in a completely customized workflow.

Ref 15.2: GitHub Actions - Docs

Ref 15.3: YouTube

15. Source code

In computing, source code is any collection of code, with or without comments, written using a human-readable programming language, usually as plain text. The source code of a program is specially designed to facilitate the work of computer programmers, who specify the actions to be performed by a computer mostly by writing source code. The source code is often transformed by an assembler or compiler into binary machine code that can be executed by the computer. The machine code might then be stored for execution at a later time. Alternatively, source code may be interpreted and thus immediately executed.

Most application software is distributed in a form that includes only executable files. If the source code were included it would be useful to a user, programmer or a system administrator, any of whom might wish to study or modify the program.

Source code

Tags: Technology,Cloud,GitHub,