J2EE is a middleware standard that has been widely adopted in the industry. It is the ideal platform for developing multitier, distributed, platform-independent enterprise applications that can scale and load-balance. The primary focus of J2EE is to provide a standard middleware infrastructure to take care of all low-level system issues, so that developers can concentrate on coding their business logic.
J2EE addresses the needs of the industry very effectively. It provides an operating system-independent environment; and resulting applications are flexible, portable, and reusable across different vendor implementations. Above all, J2EE infrastructure is capable of accommodating newer technologies and developments in the industry.
For a technical overview of J2EE, please read my next article "Inside J2EE". To know "what J2EE is not", please refer Author's comments in the discussions.