The program [potentialsAndVolt_ampere_char.py] is designed to imitate the way electrons behave in a device called a field effect transistor. It creates 3D graphs showing the electrical potential and electric field [reliefBuilder.py]. The program can also create a graph that shows how voltage and current are related. The comments in the program are written in Ukrainian, but you can use Google Translate to understand them. If you want to see an animation of how the electrons move, you can run another file called "cartoon." This will create images of the electrons' positions at different times. You can then use a program like PicGif to turn these images into an animated GIF. The animation will show how the electrons move in a 2D transistor, with the source at the bottom left, the drain at the bottom right, and the gate in the middle at the bottom.