Web container
A Web container handles requests for servlets, JSP (JSP) files, and other types of files that include server-side code. The Web container creates servlet instances, loads and unloads servlets, creates and manages request and response objects, and performs other servlet management tasks.
The Web server plug-ins, provided by the WAS, help supported Web servers pass servlet requests to Web containers.
See Also
Webapplications: Resources for learning