The document discusses Apache Karaf, an open source OSGi container. It provides: 1) An introduction to OSGi and its benefits like component-based modularity and treating applications as services. 2) An overview of Apache Karaf - an OSGi container that adds features like provisioning, deployment, administration and management. 3) How to develop applications for Karaf using standard Maven structures and deploying bundles and features to the Karaf container.