The JDBC API supports both two-tier and three-tier processing models for database access.
In the two-tier model, a Java application talks directly to the data source. This requires a JDBC driver that can communicate with the particular data source being accessed. A user's commands are delivered to the database or other data source, and the results of those statements are sent back to the user. The data source may be located on another machine to which the user is connected via a network.
The JDBC API consist of these 2 major interfaces sets: JDBC API, for application writersJDBC driver API, for driver writers
JDBC drivers fall in 1 of the four given categories. Given figure shows that applets & applications access databases through JDBC API, by using pure Java JDBC driver. JDBC Architecture
JDBC calls are converted by such kind of drivers to network protocol. This allows client machines