The Wolfram Workbench provides tools for developing solutions and applications based on Wolfram products.
This section of the Workbench documentation gives you information that is specific to working on webMathematica.
webMathematica is a version of Mathematica that runs inside a web server. It lets you add interactive calculations and visualization to a web site. This documentation gives information about working with webMathematica in the Wolfram Workbench. You can find more about webMathematica from the Wolfram Research website, http://www.wolfram.com/products/webmathematica/index.html. More details about programming for webMathematica and setting up a webMathematica server are found in the reference section of this documentation.
The webMathematica tools in the Wolfram Workbench allow you to start and stop your server, create and develop webMathematica material in a project, deploy your material to the server, and test it out on the server. The combination makes the Workbench into an extremely useful productivity tool for webMathematica development.
More information about what the Wolfram Workbench is and how it fits with other Wolfram technologies can be found at http://www.wolfram.com/solutions/workbench.