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GitHub is the largest code host on the planet, hosting over 21.4 million repositories. It is unarguably the most widely used tool by developers worldwide.
SpecsUpdate
Pros
Pro Large community
GitHub is the largest code host on the planet with over 21.4 million hosted repositories and many users. It's unarguably the largest VCS used by developers worldwide and as such, it has a vibrant community that follows it resulting in many guides and tutorials for new users. Even experienced developers can always find an answer to any question they may have.
Pro GitHub makes it easy to find open source projects
GitHub is the largest host in the world for open source projects. Developers from all over the world fork and work on countless projects hosted on it.
GitHub's search box is a powerful tool that allows developers to find open source projects in areas they are interested in and where they can immediately start to contribute.
GitHub also has a page dedicated solely at exploring and finding open source projects, grouping them by each topic they cover. In the same view, GitHub displays trending repositories and sorting them by day, week or month.