What is the difference between Repository Parameter and Repositories Collection ??

Repository parameters are enable you to specify that certain property values should be parameterized, but leave the actual parameterization to be defined in each test that is associated with the object repository that contains the parameterized test object property values.

Repository parameters are useful when you want to create and run tests on an object that changes dynamically.

Repositoriescollection is a collection of object that enables you to programmatically manage the run-time collection of shared object repository files associated with the current action.