GitHub (originally known as Logical Awesome LLC)[3] is a web-based hosting service for version control using git. It is mostly used for computer code. It offers all of the distributed version control and source code management (SCM) functionality of Git as well as adding its own features. It provides access control and several collaboration features such as bug tracking, feature requests, task management, and wikis for every project.[4]

GitHub offers plans for both private repositories and free accounts[5] which are commonly used to host open-source software projects.[6] As of April 2017, GitHub reports having almost 20 million users and 57 million repositories,[7] making it the largest host of source code in the world.[8]

Company history

The shading of the map illustrates the number of users as a proportion of each country's Internet population. The circular charts surrounding the two hemispheres depict the total number of GitHub users (left) and commits (right) per country.

On 1st March 2008, Chris Wanstrath mentioned in a blog post[9] that Github had 2000 users.

On 24 February 2009, GitHub team members announced, in a talk at Yahoo! headquarters, that within the first year of being online, GitHub had accumulated over 46,000 public repositories, 17,000 of which were formed in the previous month alone. At that time, about 6,200 repositories had been forked at least once and 4,600 had been merged.

On 5 July 2009, GitHub announced that the site was now harnessed by over 100,000 users. On 27 July 2009, in another talk delivered at Yahoo!, Tom Preston-Werner announced that GitHub had grown to host 90,000 unique public repositories, 12,000 having been forked at least once, for a total of 135,000 repositories.[10]

On 25 July 2010, GitHub announced that it hosts 1 million repositories.[11] On 20 April 2011, GitHub announced that it is hosting 2 million repositories.[12]

On 2 June 2011, ReadWriteWeb reported that GitHub had surpassed SourceForge and Google Code in total number of commits for the period January to May 2011.[13]

On 9 July 2012, Peter Levine, general partner at GitHub's investor Andreessen Horowitz, stated that GitHub had been growing revenue at 300% annually since 2008 "profitably nearly the entire way".[14]

On 16 January 2013, GitHub announced it had passed the 3 million users mark and was then hosting more than 5 million repositories.[15] On 23 December 2013, GitHub announced it had reached 10 million repositories.[16]

In June 2015, GitHub opened an office in Japan that is its first office outside of the U.S.[17]

On 29 July 2015, GitHub announced it had raised $250 million in funding in a round led by Sequoia Capital. The round valued the company at approximately $2 billion.[18]

In 2016, GitHub was ranked No. 14 on the Forbes Cloud 100 list.[19]

With the first release on July 21, 2017, Brave web browser features Github as one of its default search engines.[20]

On 28 February 2018, GitHub fell victim to the largest distributed denial-of-service (DDoS) attack in history, reaching a peak of about 1.35 terabits per second. [21]


On 3 December 2014, GitHub was blocked in Russia for a few days over user-posted suicide manuals.[22]

On 31 December 2014, GitHub was blocked in India (along with 31 other Websites) over pro-ISIS content posted by users.[23] On 10 January 2015, GitHub was unblocked. Again, on 12 Sep 2015, GitHub was blocked all over India. The site was unblocked soon after.

On 26 March 2015, GitHub fell victim to a massive distributed denial-of-service (DDoS) attack that lasted for more than 118 hours.[24] The attack, which appeared to originate from China, primarily targeted GitHub-hosted user content describing methods of circumventing Internet censorship.[25][26][27]

On 8 October 2016, GitHub access was blocked by the Turkish government to prevent email leakage of a hacked account belonging to the country's Energy Minister.[28]

Harassment allegations

In March 2014, GitHub programmer Julie Ann Horvath alleged that founder and CEO Tom Preston-Werner and his wife Theresa engaged in a pattern of harassment against her that led to her leaving the company.[29] In April 2014, GitHub released a statement denying Horvath's allegations.[30][31] However, following an internal investigation, GitHub confirmed the claims. GitHub's CEO Chris Wanstrath wrote on the company blog, "The investigation found Tom Preston-Werner in his capacity as GitHub's CEO acted inappropriately, including confrontational conduct, disregard of workplace complaints, insensitivity to the impact of his spouse's presence in the workplace, and failure to enforce an agreement that his spouse should not work in the office."[32] Preston-Werner then resigned from the company. In 2017 more allegations were made of discriminatory and unsupportive behavior at Github by a developer, who had been recruited following a commitment by Github to improve its diversity and inclusivity.[33]


GitHub's mascot, Mona, is a female anthropomorphized "octocat" with five octopus-like arms.[34][35] The character was created by graphic designer Simon Oxley as clip art to sell on iStock,[36] a website that enables designers to market royalty-free digital images.

GitHub became interested in Oxley's work after Twitter selected a bird that he designed for their own logo.[37] The illustration GitHub chose was a character that Oxley had named Octopuss.[36] Since GitHub wanted Octopuss for their logo (a use that the iStock license disallows), they negotiated with Oxley to buy exclusive rights to the image.[36]

GitHub renamed Octopuss to Octocat,[36] and trademarked the character along with the new name.[34] Later, GitHub hired illustrator Cameron McEfee to adapt Octocat for different purposes on the website and promotional materials; McEfee and various GitHub users have since created hundreds of variations of the character.[38]

Organizational structure

GitHub, Inc. was originally a flat organization with no middle managers; in other words, "everyone is a manager" (self-management).[39] Employees can choose to work on projects that interest them (open allocation). However, salaries are set by the chief executive.[40][needs update]

In 2014, GitHub, Inc. introduced a layer of middle management.[41]


GitHub.com was a start-up business, which in its first years provided enough revenue to be funded solely by its three founders and start taking on employees.[42] In July 2012, four years after the company was founded, Andreessen Horowitz invested $100M in venture capital.[4] In July 2015 GitHub raised another $250M of venture capital in a series B round. Investors were Sequoia Capital, Andreessen Horowitz, Thrive Capital and other venture capital funds.[43] As of August 2016, GitHub was making $140M in Annual Recurring Revenue.[44]



Development of the GitHub platform began on 19 October 2007.[45][46][47] The site was launched in April 2008 by Tom Preston-Werner, Chris Wanstrath, and PJ Hyett after it had been made available for a few months prior as a beta release.[48]

Projects on GitHub can be accessed and manipulated using the standard Git command-line interface and all of the standard Git commands work with it. GitHub also allows registered and non-registered users to browse public repositories on the site. Multiple desktop clients and Git plugins have also been created by GitHub and other third parties that integrate with the platform.

The site provides social networking-like functions such as feeds, followers, wikis (using wiki software called Gollum) and a social network graph to display how developers work on their versions ("forks") of a repository and what fork (and branch within that fork) is newest.

A user must create an account in order to contribute content to the site, but public repositories can be browsed and downloaded by anyone. With a registered user account, users are able to discuss, manage repositories, submit contributions to others' repositories, and review changes to code.

The software that runs GitHub was written using Ruby on Rails and Erlang by GitHub, Inc. developers Chris Wanstrath,[49] PJ Hyett, and Tom Preston-Werner.


GitHub is mostly used for code.

In addition to source code, GitHub supports the following formats and features:

  • Documentation, including automatically rendered README files in a variety of Markdown-like file formats (see README files on GitHub)
  • Issue tracking (including feature requests) with labels, milestones, assignees and a search engine
  • Wikis
  • Pull requests with code review and comments
  • Commits history
  • Graphs: pulse, contributors, commits, code frequency, punch card, network, members
  • Integrations Directory[50]
  • Unified and split diffs
  • Email notifications
  • Option to subscribe someone to notifications by @ mentioning them.[51]
  • Emojis[52]
  • GitHub Pages: small websites can be hosted from public repositories on GitHub. The URL format is https://username.github.io.[53]
  • Nested task-lists within files
  • Visualization of geospatial data
  • 3D render files that can be previewed using a new integrated STL file viewer that displays the files on a "3D canvas".[54] The viewer is powered by WebGL and Three.js.
  • Photoshop's native PSD format can be previewed and compared to previous versions of the same file.
  • PDF document viewer

Licensing of repositories

GitHub's Terms of Service do not require public software projects hosted on GitHub to meet the Open Source Definition. For that reason, it is essential for users and developers intending to use a piece of software found on GitHub to read the software license in the repository (usually found in a top-level file called "LICENSE", "LICENSE.txt", or similar) to determine if it meets their needs[citation needed]. The Terms of Service state, "By setting your repositories to be viewed publicly, you agree to allow others to view and fork your repositories."[55]

GitHub Enterprise

GitHub Enterprise is similar to GitHub's public service but is designed for use by large-scale enterprise software development teams where the enterprise wishes to host their repositories behind a corporate firewall.[56]


GitHub also operates other services: a pastebin-style site called Gist[48] that is for hosting code snippets (GitHub proper is for hosting larger projects), and a slide hosting service called Speaker Deck.

Tom Preston-Werner presented the then-new Gist feature at a punk rock Ruby conference in 2008.[57] Gist builds on the traditional simple concept of a pastebin by adding version control for code snippets, easy forking, and SSL encryption for private pastes. Because each "gist" has its own Git repository, multiple code snippets can be contained in a single paste and they can be pushed and pulled using Git. Further, forked code can be pushed back to the original author in the form of a patch, so gists (pastes) can become more like mini-projects.

Education program

GitHub launched a new program called the GitHub Student Developer Pack to give students free access to popular development tools and services. GitHub partnered with Bitnami, Crowdflower, DigitalOcean, DNSimple, HackHands, Namecheap, Orchestrate, Screenhero, SendGrid, Stripe, Travis CI and Unreal Engine to launch the program.[58]

GitHub Marketplace service

GitHub also provides some software as a service integrations for adding extra features to projects. Those services include:

  • Waffle.io: Project management for software teams. Automatically see pull requests, automated builds, reviews, and deployments across all of your repositories in GitHub.
  • Rollbar: Integrate with GitHub to provide real time debugging tools and full-stack exception reporting. It is compatible with all well used code languages, such as JavaScript, Python, .Net, Ruby, PHP, Node.js, Android, iOS, Go, Java and C#.
  • Codebeat: For automated code analysis specialized in web and mobile developers. The supported languages for this software are: Elixir, Go, Java, Swift, JavaScript, Python, Ruby, Kotlin, Objective-C, TypeScript.
  • Travis CI: To provide confidence for your apps while doing test and ship. Also gives full control over the build environment, to adapt it to the code. Supported languages: Go, Java, JavaScript, Objective-C, Python, PHP, Ruby and Swift.
  • GitLocalize: Developed for teams that are translating their content from one point to another. GitLocalize automatically syncs with your repository so you can keep your workflow on GitHub. It also keeps you updated on what needs to be translated.

See also


  1. ^ "About - GitHub". GitHub. 
  2. ^ "Github.com Alexa Ranking". Alexa Internet. Retrieved January 20, 2018. 
  3. ^ "New Year, New Company". Retrieved 11 April 2016. 
  4. ^ a b Williams, Alex (9 July 2012). "GitHub Pours Energies into Enterprise – Raises $100 Million From Power VC Andreessen Horowitz". TechCrunch. Andreessen Horowitz is investing an eye-popping $100 million into GitHub 
  5. ^ "Why GitHub's pricing model stinks (for us)". LosTechies. 7 November 2012. Archived from the original on 29 June 2015. Retrieved 29 June 2015. 
  6. ^ "The Problem With Putting All the World's Code in GitHub". Wired. 29 June 2015. Archived from the original on 29 June 2015. Retrieved 29 June 2015. 
  7. ^ "Celebrating nine years of GitHub with an anniversary sale". github.com. Github. Retrieved 2017-04-11. 
  8. ^ Gousios, Georgios; Vasilescu, Bogdan; Serebrenik, Alexander; Zaidman, Andy. "Lean GHTorrent: GitHub Data on Demand" (PDF). The Netherlands: Delft University of Technology & †Eindhoven University of Technology: 1. Retrieved 9 July 2014. During recent years, GITHUB (2008) has become the largest code host in the world. 
  9. ^ Wanstrath, Chris (1 March 2008). "GitHub: Free for Open Source". Github. 
  10. ^ Dascalescu, Dan (3 November 2009). "The PITA Threshold: GitHub vs. CPAN". Dan Dascalescu's Wiki. 
  11. ^ "One Million Repositories, Git Official Blog". 25 July 2010. 
  12. ^ "Those are some big numbers, Git Official Blog". 20 April 2011. 
  13. ^ "Github Has Surpassed Sourceforge and Google Code in Popularity". During the period Black Duck examined, Github had 1,153,059 commits, Sourceforge had 624,989, Google Code and 287,901 and CodePlex had 49,839. 
  14. ^ Levine, Peter (2012-07-09). "Software Eats Software Development". 
  15. ^ "Code-sharing site Github turns five and hits 3.5 million users, 6 million repositories". TheNextWeb.com. 2013-04-11. Retrieved 2013-04-11. 
  16. ^ "10 Million Repositories". GitHub.com. 2013-12-23. Retrieved 2013-12-28. 
  17. ^ "GitHub Expands To Japan, Its First Office Outside The U.S." TechCrunch. 2015-06-04. 
  18. ^ "GitHub raises $250 million in new funding, now valued at $2 billion". Fortune. 2015-07-29. 
  19. ^ "Forbes Cloud 100". Forbes. Retrieved 31 October 2016. 
  20. ^ "Brave Browser Github page". Github. Retrieved 10 August 2017. 
  21. ^ "GitHub Survived the Biggest DDoS Attack Ever Recorded". WIRED. Retrieved 2 March 2018. 
  22. ^ "Russia Blacklists, Blocks GitHub Over Pages That Refer To Suicide". 
  23. ^ "GitHub, Vimeo and 30 more sites blocked in India over content from ISIS". thenextweb.com. The Next Web. 2014-12-31. 
  24. ^ "Large Scale DDoS Attack on github.com". github.com. GitHub. 27 March 2015. Retrieved 31 March 2015. 
  25. ^ "Last night, GitHub was hit with massive denial-of-service attack from China". theverge.com. The Verge. 27 March 2015. Retrieved 27 March 2015. 
  26. ^ "U.S. Coding Website GitHub Hit With Cyberattack". wsj.com. The Wall Street Journal. 29 March 2015. Retrieved 29 March 2015. 
  27. ^ "Massive denial-of-service attack on GitHub tied to Chinese government". arstechnica.com. Ars Technica. 31 March 2015. Retrieved 1 April 2015. 
  28. ^ "Turkey blocked GitHub and Dropbox to hide leaks – reports". 
  29. ^ Biddle, Sam; Tiku, Nitasha (17 March 2014). "Meet the Married Duo Behind Tech's Biggest New Harassment Scandal". Vallywag. Gawker. Archived from the original on 17 March 2014. Retrieved March 17, 2014. 
  30. ^ Miller, Claire Cain (April 21, 2014). "GitHub Founder Resigns After Investigation". Bits. The New York Times. 
  31. ^ Wilhelm, Alex (April 21, 2014). "GitHub Denies Allegations Of "Gender-Based Harassment," Co-Founder Preston-Werner Resigns". TechCrunch. 
  32. ^ "Follow up to the investigation results". April 28, 2014. 
  33. ^ Ehmke, Coraline Ada blog. "Antisocial Coding: My Year at GitHub,". Retrieved July 5, 2017. 
  34. ^ a b "GitHub Octodex FAQ". github.com. Retrieved 21 September 2015. 
  35. ^ Jaramillo, Tony (24 November 2014). "From Sticker to Sculpture: The making of the Octocat figurine". The GitHub Blog. GitHub. Retrieved 2017-04-19. 
  36. ^ a b c d DeAmicis, Carmel (8 July 2013). "Original GitHub Octocat designer Simon Oxley on his famous creation: "I don't remember drawing it"". PandoDaily. Retrieved 2017-04-19. 
  37. ^ Campbell-Dollaghan, Kelsey (26 April 2013). "Meet the Accidental Designer of the GitHub and Twitter Logos". Co.Design. Fast Company. Retrieved 2017-04-19. 
  38. ^ McEfee, Cameron (12 May 2016). "The Octocat—a nerdy household name". CameronMcEfee.com. Cameron McEfee. Retrieved 2017-04-19. 
  39. ^ Tomayko, Ryan (2 April 2012). "Show How, Don't Tell What - A Management Style". Retrieved 28 August 2013. 
  40. ^ Hardy, Quentin. "Dreams of 'Open' Everything". New York Times. 
  41. ^ Evelyn, Rusli (17 July 2014). "Harassment claims make startup GitHub grow up". Wall Street Journal. Retrieved 18 July 2014. 
  42. ^ Michael, Carney (20 June 2013). "GitHub CEO explains why the company took so damn long to raise venture capital". PandoDaily. Retrieved 10 July 2014. 
  43. ^ Lardinois, Frederic. "GitHub Raises $250M Series B Round To Take Risks". TechCrunch. Retrieved 2016-07-04. 
  44. ^ Plassnig, Moritz. "GitHub is making $140M in ARR". Medium. Retrieved 2016-12-19. 
  45. ^ Weis, Kristina (2014-02-10). "GitHub CEO and Co-Founder Chris Wanstrath Keynoting Esri's DevSummit!". in 2007 they began working on GitHub as a side project 
  46. ^ Preston-Werner, Tom (19 October 2008). "GitHub Turns One!". GitHub. Retrieved 2014-03-28. 
  47. ^ Wanstrath, Chris (7 December 2009). "The first commit was on a Friday night in October, around 10 pm". Retrieved 2017-11-04. 
  48. ^ a b Catone, Josh (24 July 2008). "GitHub Gist is Pastie on Steroids". GitHub hosts about 10,000 projects and officially launched in April of this year after a beta period of a few months. 
  49. ^ "Interview with Chris Wanstrath". Doeswhat.com. 2012-03-06. Retrieved 2013-02-26. 
  50. ^ "Integrations Directory". GitHub. Retrieved 30 April 2016. 
  51. ^ "Mention @somebody. They're notified". GitHub. Retrieved 30 April 2016. 
  52. ^ "Github Help / Categories / Writing on GitHub". Github.com. Retrieved 30 April 2016. 
  53. ^ "GitHub Pages". 
  54. ^ Weinhoffer, Eric (2013-04-09). "GitHub Now Supports STL File Viewing". 
  55. ^ "GitHub Terms of Service - User Documentation". Help.github.com. 2016-02-11. Retrieved 2016-12-05. 
  56. ^ "Introducing GitHub Enterprise". GitHub. Retrieved 13 July 2014. 
  57. ^ Preston-Werner, Tom (2008-07-20). God's memory leak - a scientific treatment. RubyFringe. Retrieved 2014-10-21. He previewed the upcoming git feature gist 
  58. ^ Lardinois, Frederic (7 October 2014). "GitHub Partners With Digital Ocean, Unreal Engine, Others To Give Students Free Access To Developer Tools". TechCrunch. Retrieved 7 October 2014. 

External links