A Python module is an external class or set of functions that exist outside the main file of your program. This can be something that you built yourself, or it can be provided by the community.

Whatever file you give to the interpreter at startup becomes main. It doesn't matter the name. In both cases, __name__ is the name of the module. However, it will only be set to __main__ if running as ...

The if __name__ == "__main__": statement checks if the script is being run as the main program. If it is, it calls the greet() function with the name "Alice". If this script were imported as a module ...