Workflow quality features like statuses, pre-receive hooks, protected branches, and required status checks help collaborators make contributions that meet conditions set by organization and repository administrators.
About statuses
Statuses let you know if your commits meet the conditions set for the repository you're contributing to.
Working with protected branches
If you're working on a protected branch, you won't be able to make irrevocable changes to the branch. Repository administrators may also enable required status checks or required pull request reviews on the protected branch, which will add additional requirements to the mergeability of your work on the protected branch.
Working with pre-receive hooks
Pre-receive hooks enforce rules for contributions before commits may be pushed to a repository.