What Is Difference Between Web Server And Application Server?

The term Web server can mean one of two things:

A computer that is responsible for accepting HTTP requests from clients, which are known as Web browsers, and serving them HTTP responses along with optional data contents, which usually are Web pages such as HTML documents and linked objects (images, etc.).
A computer program that provides the functionality described in the first sense of the term.

while,

An application server is a server computer on a computer network dedicated to running certain software applications (as opposed to e.g. a file server or print server).

Generally, an application server is a software engine that delivers applications to client computers. Moreover, an application server should handle most, if not all, of the business logic and data access of the application. The main benefits of application server technology are ease of application development and centralization.

Although the term application server applies to all platforms, it has become heavily identified with the Sun Microsystems J2EE platform; however, it has also come to encompass servers of web-based applications, such as integrated platforms for e-commerce, content management systems, affiliate management systems and occasionally, even applied to simplistic web-site page builders. The paradigm is more similar to mainframe based applications than traditional client-server.

A Web Server understands and supports only HTTP protocol whereas an Application Server supports HTTP,TCP/IP and many more protocols. Also many more features such as Caches,Clusters,Load Balancing are there in Application Servers which are not available in Web Servers. We can also Configure Application Servers to work as Web Server. In short, Applicaion Server is a super set of which Web Server is a sub set.

There is some confusion about the difference between an application server and a Web server. An application server is defined as a development environment by which developers can not only create, but they can also test and execute application components easily. An application server is usually based on J2EE and can be used to run EJB or other components of the Java programming language.

On the other hand, a Web server is defined as a content server which has basically been designed for the purpose of creating as well as deploying websites on the Internet as well as for the purpose of serving up more content than an application server. However, the main point of similarity between an application server and a Web server is that both application servers and Web servers use Web interfaces.