A Simple Calculator to perform simple arithmetic operation USING TKINTER GUI TOOLKIT: Tkinter is an inbuilt Python module used to create simple GUI apps.It is the most commonly used module for GUI apps in the Python. Tkinter comes with Python default.Tkinter was also used in the development of Python editor,IDLE. Few methods used in Tkinter Toolkit: tkinter.Tk() to initialize window manager. tkinter.title() to give title to the window. mainloop() to display the window. and many more functions