Google

JDBC Thin Client

Source: oracle.com
The JDBC Thin Client is a pure Java, Type IV driver. It is lightweight and easy to install. It provides high performance, comparable to the performance provided by JDBC Oracle Call Interface (OCI) driver. The JDBC Thin driver is written entirely in Java, and therefore, it is platform-independent. Also, this driver does not require any additional Oracle software on the client side.
The JDBC Thin driver communicates with the server using TTC, a protocol developed by Oracle to access data from Oracle Database. It can be used for application servers as well as for applets. The driver allows a direct connection to the database by providing an implementation of TCP/IP that implements Oracle Net and TTC on top of Java sockets. Both of these protocols are lightweight implementation versions of their counterparts on the server. The Oracle Net protocol runs over TCP/IP only.
The JDBC Thin driver can be used on both client side and server side. On the client side, you use this driver to access application servers, from a Java method to access data on Oracle Database, and to access applets. On the server side, this driver is used to access a remote Oracle Database instance or another session on the same database. Typically, on the server side, this driver is used to access the Oracle Database from a Java stored procedure on the database.