A Project House is a system to hold your projects and it is located under its root directory, e.g. /home/to/my/ProjectHouse/.
The caretaker is a command that creates and maintaines such a Project House. In particular, it can start a server that provides a GUI web browsers to very intuitively manage any number of single projects.
See:
The home page of the package contains a list of resources, a description of the installation and an overview of all versions.
The handbook is the primary source for information.
The forum is a news group dedicated to this program. This is the place for all communications and bug reports.