You can use BeanShell interactively for Java experimentation and debugging or as a simple scripting engine for your applications. In short: BeanShell is a dynamically interpreted Java, plus some useful stuff. Another way to describe it is to say that in many ways BeanShell is to Java as Tcl/Tk is to C: BeanShell is embeddable - You can call BeanShell from your Java applications to execute Java code dynamically at run-time or to provide scripting extensibility for your applications. Alternatively, you can call your Java applications and objects from BeanShell; working with Java objects and APIs dynamically. Since BeanShell is written in Java and runs in the same space as your application, you can freely pass references to "real live" objects into scripts and return them as results.