As far as I understand a web application is a rich, dynamic webpage, containsing lots of user-generated content, achieved via certain code behind the static webpage.
What are the key components of the above? Is it OK to say that you require a standard HTML website and some sort of framework that would generate the dynamics for you from code written in some language (these include GWT, Play etc)?
Broadly you will find a web app with these components
With HTML, Programming Language(Java, .Net, PHP) doing the server side work