Pure Data is a graphic programming environment that allows you to build your own software. In this part of the series, Dr. Lawrence W. Moore show how to build a simple modular synthesizer. Because the construction is modular, different components can be added with each upcoming episode. In this episode he shows how to receive MIDI data into pd and how to take that data, display it, and get it ready to be routed throughout the rest of the synthesizer. There are a few logical strategies to controlling the flow of the data that are discussed. One learns how to receive and utilize note, velocity, modulation wheel, sustain pedal, and pitch bend information.