A local instance is always a .dat file and accessed directly, not via TIBCO Rendezvous.
A repository instance is a named collection of data, usually metadata and configuration data that is persistently stored. A local repository instance is stored on the local file system and directly accessed by the client. A remote repository instance is managed by a repository server and accessed by a client using TIBCO Rendezvous.
See Introduction for information on the operations you can perform.
A repository directory is a container for one or more directories as well as one or more objects. Directories are used for organizing objects so that they can then be referred to unambiguously.
A repository object is a container for the data. Data are organized as an ordered list of name:value pairs called an association list. In effect, an object is a named association list. The term object is used although there is no notion of inheritance or information hiding, nor does the object have any methods.