Appserver example

Jboss
weblogic etc
are the servers which can manage the lifecycle of the app or business logic residing in servlets and Ejbs and supply dynamic contents according to response .


webserver example

apache
are simple programs listening on port 80 to send static html pages to the browser which has requested for the page .

In current scenario these webservers are connected at the backend with appservers and supply the pages .

Often times in casual conversation, they are used interchangeably. However, a Web Server like Apache is designed and optimized to serve up static Web Pages in HTML. You can use connectors to have it run a CGI script such as Perl, PHP, C/C++ or Java etc. Then, it can become an Application Server (appserver). Some AppServers like Tomcat are designed and optimized to server up JSP/Servlets and what one would call a dynamic Web Application rather than Static HTML. That doesn't mean that they can't serve up static html, but the are not optimized for it.

Hope this helps.

Stephen McConnell