The last line of this answer prompted me to ask this question . I know to know at a conceptual level the difference between Git and GitHub .
Git is the distributed version control system. Git is responsible for keeping track of changes to content (usually source code files), and it provides mechanisms for sharing that content with others.
GitHub is a company that provides Git repository hosting. If your team has a shared repository on GitHub, you could conceivably use GitHub without ever looking at its website. But, the website provides a lot of value on top of the core Git repository.
GitHub also developed graphical Git clients: GitHub for Mac and GitHub for Windows. Each is an application that lets you interact with Git repositories without using the command line.
Concepts from Git: Repositories, branches, remotes, committing, pushing, pulling, merging, rebasing, reverting, and cherry-picking.
Concepts from GitHub: Pull requests, issues, wikis, forking someone else's repository, Gists, github.com.