THIS IS A TEST INSTANCE. ALL YOUR CHANGES WILL BE LOST!!!!
...
Apache Sling is a web framework that uses a JCR content repositoryJava Content Repository, such as Apache Jackrabbit, to store and manage content.
...
As the first web framework dedicated to JCR content repositoriesJSR-170 Java Content Repositories, Sling makes it very simple to implement simple applications, while providing an enterprise-level framework for more complex applications.