This first-time user guide provides introductory material to BJT on nanoHUB. It includes a tour of the Rappture interface, which notes key inputs and typical outputs, and an introduction to the workings of NPN and PNP type BJT. We discuss the default simulation (what happens if you don't change any inputs, and just hit "Simulate") as well as the limitations of the tool. Provided also are a few examples that allow the users to understand the scope of the tool. Lastly, we offer final comments and several references for further study.