Every GitHub repository has the option to communicate with a web server whenever the repository is pushed to. These webhooks can be used to update an external issue tracker, trigger CI builds, update a backup mirror, or even deploy to your production server.
Webhooks can be added to any repository owned by an individual or organization, on a per-repository basis.
Webhooks rely on an external server. For technical instructions on creating a new webhook or adding one to your repository, please visit our Developer website.