The applet is meant to model the behavior of an Agent Architecture where many agent programs are sending data to a single intelligent collector. The red vertical models the current time, and the green vertical models the latest time for which data has been collected from all agents.
Often we send software engineers to build a system like this, without really knowing what it looks like. This applet is 150 lines of code, and lays things quite bare.
If the applet fails to load, download the Jar file here and then click to run it locally. The Jar is signed with a self generated key. That's the best I can do, short of buying a code signing cert. Even still, you may see various security warnings like the one below. The applet is safe to run.