servers

Definition of Apache server:

 Apache is generally recognized as the world's most popular Web server (HTTP server). Originally designed for Unix environments, the Apache Web server has been ported to Windows and other network operating systems. The name "Apache" derives from the word "patchy" that the Apache developers used to describe early versions of their software.
                                                  The Apache Web server provides a full range of Web server features, including CGI, SSL, and virtual domains. Apache also supports plug-in modules for extensibility. Apache is free software, distributed by the Apache Software Foundation that promotes various free and open source advanced Web technologies

 Application server

An application server can be either a software framework that provides a generalized approach to creating an application-server implementation, regard to what the application functions are, or the server portion of a specific implementation instance. In either case, the server's function is dedicated to the efficient execution of procedures (programs, routines, scripts) for supporting its applied applications.

Application Server vs Web Server

1. Application Server supports distributed transaction and EJB. While Web Server only supports Servlets and JSP.

 

2. Application Server can contain web server in them. most of App server e.g. JBoss or WAS has Servlet and JSP container.

3. Though its not limited to Application Server but they used to provide services like Connection pooling, Transaction management, messaging, clustering, load balancing and persistence. Now Apache tomcat also provides connection pooling.

4. In terms of logical difference between web server and application server. web server is supposed to provide http protocol level service while application server provides support to web service and expose business level service e.g. EJB.

5. Application server are more heavy than web server in terms of resource utilization.