PrF UG files project types
Understanding Project Types
Every Protege-Frames project stores two kinds of information:
Protege-specific information, stored in a .pprj (Protégé project) file
Information about the project ontology (classes, slots, etc.) and project instances, stored in one or more additional files.
No matter which format you choose, the information specific to the Protege-Frames interface is saved in a .pprj file. You can create, open, and save your projects directly via the .pprj file. You do not need to name or access any other files unless you wish to import a project.
Choosing the project type, or backend, determines how the project ontology and instances are stored. Protege-Frames supports three file formats:
Protege Files (the default) creates two text files in Protege-Frames format. See Protege Files.
Protege Database creates the project as a table in a JDBC database. To do this, you must have a database installed and configured on your system. See Protege Database Format.
Experimental XML saves the project in XML format. See Experimental XML Format.
Normally, for a Protege-Frames project, you would select Protege Files or Experimental XML. If you have installed support for additional backends, e.g., if you selected BASIC + OWL as your installation, you will see additional file formats.
If you decide you wish to change your project type, e.g., from Protege Files to Experimental XML, you can convert your project. This changes the format of the backend, while leaving the .pprj file unchanged. Protege still uses the .pprj file to access the project. You should not see a difference within Protege.
You can also export a project to CLIPS or HTML formats. In this case, the project itself stays the same, but a snapshot of the current version is created in the selected format.