difference between web application and web site.

Please any one tell me difference between web application and web site.

A website usually refers to the front-end interface through which the public interact with your business online.Websites are typically informational in nature with a limited amount of advanced functionality. Simple websites consist primarily of static content where the data displayed is the same for every visitor and content changes are infrequent. More advanced websites may sport features such as eCommerce, content management and interactive content.

WhereAS
A web application or Rich Internet Application (RIA) usually includes a website component but features additional advanced functionality to replace or enhance existing business processes. The interface design objective behind a web application is to simulate the intuitive, immediate interaction a user experiences with a desktop application.

Web applications frequently integrate with existing business IT infrastructure such as accounting packages, stock management systems, ERP, etc.