Hi Adrian,
OLE DB allows access to information from a wide range of databases. It is a more generalized and more efficient strategy for data access than ODBC because it is based on the Component Object Model (COM). It is also newer, more advanced and designed to be compatible with a wider selection of DB technologies. It encompasses ODBC functionality.
I think this link will be helpful. It discusses extensively the pros and cons of each technology.
OLE DB or ODBC? | SQL Server content from SQL Server Pro
Best Regards
Fernando