- BSON - classes for working with the BSON data format. 
- BSON Record Codec - classes for encoding and decoding between Java records and the BSON data format. 
- Core - classes that contain essential driver functionality. 
- Java Driver (modern API) - classes for the current driver API. 
- Java Driver (legacy API) - classes that support the legacy driver API. To learn how to upgrade from the legacy API to the modern API from the Migrate from the Legacy API documentation.