Database engine refers to the code that carries out the actual database function. For example, MySQL comes with a database engine, but it also comes with components that allow a server to serve up connections to the database engine, allow a client to contact the server, etc.. These components are not a part of the database engine of MySQL. ooSQLite works by making calls into the SQLite database engine, (which is embedded within ooSQLite.) Within this documentation, a reference to the database engine means the SQLite database engine. In places in the documentation, the SQLite database engine is stated explictly. In places where the SQLite part is left off, the SQLite part is implicit.