Properties file used by Rational Rhapsody, a visual development program designed for systems engineers and software developers; contains a list of properties for a data model created with Rational Rhapsody; similar to a .PTY file, but is user-controlled and is created specifically for multi-user environments.
PRP files use LL1 syntax, which can be recursively parsed by the program. They typically include a list of subjects that define different aspects of the model. Each subject may include a list of metaclasses, which are sub-properties of each subject.
NOTE: PRP files are also used by Rational Rose, the predecessor to Rhapsody.