Experiment 2: The Null program interface test. The Null Program is the simplest program that one can do, and is a place to start. The null program above, copied and pasted from Arduino website, contains two basic sections the void setup() section and the void loop() section. The void setup() section is where the code instruction are read and implemented once, like identifying a variable, and the void loop() section is for code that is repeated over and over again. Thirdly there are double forward slashes (//) before comments. These tell the processor to ignore this text and that the text is not an attempt at coding. Clear commenting makes quality programs.