Bitbucket vs GitHub vs GitLab

Bitbucket

• Bitbucket was launched in 2008 initially supporting Mercurial Projects. In 2010, it was acquired by Atlassian and from 2011 it also started to support Git hosting.
• It supports the Mercurial VCS(version control system) in addition to Git
• It is not open source but by buying the self-hosted version the full source code is provided.
• Bitbucket is written in Python and uses the Django web framework.
• We get free private repositories on Bitbucket
• It offers both commercial plans and free accounts. It offers free accounts with an unlimited number of private repositories
• Imports existing Git projects from Excel, Github, etc.
• Some remarkable features of Bitbucket are
  1. Issue tracking
  2. REST APIs to build third-party applications which can use any development language
  3. Code search is possible
  4. Pull requests with code review and comments
  5. Snippets that allow developers to share code segments or files

GitHub

• GitHub was launched in 2008. It is a git-based repository hosting platform, currently owned by Microsoft.
• It only hosts projects that use the Git VCS
• It is free for public repositories and for private ones it is paid.
• GitHub is written using Ruby and Erlang
• It has something called Gists(a way to share code snippets)
• It comes with its own Wiki and issues tracking system.
• Here, we can decide if someone gets read or write access to a repository.
• It's the largest repository host with more than 38+ million projects.
• It provides support for an online web-based VS code editor.
• It has size limitations. The file size can’t be more than 100 Mb while the repository can host 2GB of information.
• Some remarkable features of GitHub are
  1. Commit History can be seen
  2. Graphs: pulse, contributors, commits, code frequency, members of it.
  3. Pull requests with code review and comments
  4. Issue Tracking
  5. Email notifications

GitLab

• GitLab was launched as a project in 2011 providing an alternative to the available repository management solutions. But the site GitLab.com was launched in 2012
• It does almost everything that GitHub does, so it is like Github, but here we have free private repositories that Github doesn't
• GitLab Community Edition is free and open-sourced.
• Here we can set and modify people’s permissions according to their roles.
• In this, you can attach any file to any issue. You can’t do this inside GitHub.
• The source code of GitLab Community Edition is available on their website
• It has a relatively slow interface
• It supports Git import
• Some remarkable features of GitHub are
  1. Issue Tracker
  2. Commit graph and reporting tools
  3. Create new issues from the Issue Board
  4. Ease of migration from other providers

Now which one to choose and when? 

If you want to just contribute to other open source projects then use GitHub. These days GitHub acts as online portfolio for a person, where one can upload some of his own projects and mention the GitHub account in his resume. Having a active GitHub account helps to distinguish one from others, and shows how much he has worked for open source. While GitLab is a decent solution, especially for Digital Ocean and GitLab is free for private repositories while GitHub charges. Many organizations uses GitLab while they want there codebase to be private. Bitbucket restricts you to work with only 5 people for free, GitLab.com is completely free. So if you want to work with Digital Ocean then GitLab is best and when you want to You want to host your 1000 repositories and 100 colleagues somewhere then GitLab.com is the solution. Bitbucket is one of the most popular while it comes at organization's point of view. More organizations host their projects in Bitbucket compared to GitLab, due to its user friendly interface. Bitbucket Cloud has Mercurial support. Bitbucket also offers free private repositories so only members can access the codebase. So if you are a organization and want to host your project, then go for Bitbucket, and even you can individually host some projects there too, apart from organization.