Content for Web Applications

A web application is a website that contains pages with partly or entirely undetermined content. The final content of these pages is determined only when a visitor requests a page from the web server. Because the final content of the page varies from request to request based on the visitor’s actions, this kind of page is called a dynamic page. (source)

Here's an interesting article about writing content for applications. Not the content that goes around the application, but the content for the application itself. You know, buttons, labels, help desk, directions.