In PersistenceMapping - how things are represented in a database - AutoGuid represents an dbgenerated Guid value.

As you state that you are new to MDriven you will probably not be interested in overriden persitence mapping just yet -> forget about AutoGuid for now.

Common types for attributes are the simple native types:

String (size limited in db) Text (Text in db - no size limit) Double Decimal Integer DateTime Boolean Blob (Binary data byte[] -combine with setting for BlobType) Guid