hub

TLDR

Clone a repository using its slug (owners can omit the username)

$ hub clone [username]/[repo_name]

Create a fork of the current repository (cloned from another user) under your GitHub profile

$ hub fork

Push the current local branch to GitHub and create a PR for it in the original repository

$ hub push [remote_name] && hub pull-request

Create a PR of the current (already pushed) branch, reusing the message from the first commit

$ hub pull-request --no-edit

Create a new branch with the contents of a pull request and switch to it

$ hub pr checkout [pr_number]

Upload the current (local-only) repository to your GitHub account

$ hub create

Fetch Git objects from upstream and update local branches

$ hub sync