0 Hi Arjun,
Oracle Spatial (formerly called SDO and before that MultiDimension), provides a way to store and retrieve multi-dimensional data in Oracle. It is primarily used for Geographical Information Systems to implement geo-reference and solve queries such as how is something related to a specific location.
Oracle Locator is free with the Oracle Database Server (EE and Standard Edition). Oracle Spatial is intended for "heavy" spatial applications. It only ships with Oracle Enterprise Edition and are separately charged.
Please refer the below links
http://www.orafaq.com/wiki/Spatial_FAQ
http://www.spatialdbadvisor.com/oracle_spatial_tips_tricks/55/oracle-locator-vs-enterprise-licensing-the-sdogeom-package
http://docs.oracle.com/html/A88805_01/sdo_intr.htm
Thanks