# {: style="height:50px"} {: style="height:50px"} ## What is passbook? passbook is an open-source Identity Provider focused on flexibility and versatility. You can use passbook in an existing environment to add support for new protocols. passbook is also a great solution for implementing signup/recovery/etc in your application, so you don't have to deal with it. ## Installation See [Docker-compose](installation/docker-compose.md) or [Kubernetes](installation/kubernetes.md) ## Screenshots  