The runner is the application that runs a job from a GitHub Actions workflow. It is used by GitHub Actions in the [hosted virtual environments](https://github.com/actions/virtual-environments), or you can [self-host the runner](https://help.github.com/en/actions/automating-your-workflow-with-github-actions/about-self-hosted-runners) in your own environment.
For more information about installing and using self-hosted runners, see [Adding self-hosted runners](https://help.github.com/en/actions/automating-your-workflow-with-github-actions/adding-self-hosted-runners) and [Using self-hosted runners in a workflow](https://help.github.com/en/actions/automating-your-workflow-with-github-actions/using-self-hosted-runners-in-a-workflow)