Having scratched my head over how all the parts fit together in a new Jasper reporting system for SugarCRM, I finally came across this article:
The first couple of paragraphs explained what all the parts are, in a way that the deliverer of the system simply could not.
Jasper Reports is the central report generating engine. It is designed to be embedded inside an application.
If you don’t have a Java application to embed Jasper Reports in, then you can use Jasper Server to provide a wrapper for you. This wrapper provides the framework to run the report in, and a repository for any resources the report may need (database connection details, images, etc).
Jasper Reports provides a web front end for end users, and also provides an API for web applications. One web application is SugarCRM, and the Zucker4Jasper plugin provides that bridge.
Finally you will want to create reports. iReport is the Java application for doing this. It looks very comprehensive, even if a bit kludgey to use (I find I can never seem to get to the window I want by following the same navigation path twice – context seems to keep jumping all over the place). It is just something to learn.