Some features described here are available in Ultimate edition only.
The term Web application is usually applied to a hierarchical set of folders with HTML, JSP, JavScript, etc. files and resources, that represent the user interface,
and Java classes, that implement the application functionality. These folders are arranged according to the standard specified for the server where the application is deployed and executed.
To ensure successful deployment and accessibility of your Web application, you need to set up its structure in accordance with the target server standard already at the development stage.
Next, most likely you will need to configure Web application elements, set initialization parameters, and define interaction with EJB, WebServices, etc.
You will need various libraries to configure these components and relations and an application descriptor that contains definitions of these components, settings, and constraints.
With IntelliJ IDEA, you can have the basic application structure automatically set up according to the required standard and get extensive coding assistance at all the stages of Web application development.