The BaseConnector consists of these components:

1. Store schemas: A vendor-neutral representation of the library domain, defined in XML and database schemas (e.g. Borrower, Loan).
2. Store: An implementation of the store schemas in a RDBMS.
3. Service layer: A set of services for accessing data in the store.
4. Service descriptor: A description of the services available from the service layer. This could be implemented using something like WADL.
5. WebLayer: A web application which presents the service layer over HTTP to clients.

The BaseConnector implements some functionality of a fully-fledged ILS, but only enough to experiment with. It does not provide enough functionality to run a library off of :)