Now that we've seen how to develop a servlet, and we can imagine how it's invoked, we can discuss some of the details of what goes on behind the scenes. For performance and scalability reasons, it's of particular interest to know how the servlet container works.
First, let's consider the term container versus an older term used to describe this entity: engine. When you think of a container, you think of a host—a mechanism for storing a resource such as a servlet. In contrast, an engine connotes a mechanism for processing, which is not at all what happens. Container is a better, more accurate term to be sure, since the real execution has to do with the code written by the servlet programmer. Interestingly, ...