The provided code is a simple To-Do List application built using the Tkinter library in Python. Let me break down the key components and functionalities of the application:

Importing Necessary Libraries: The code starts with importing the required libraries, including Tkinter for GUI development and datetime for handling date and time operations.

Creating the Tkinter Window: A Tkinter window is created with a specific size and title.

Functionality for Adding Tasks: Users can input tasks in the Entry widget provided. When the "ADD" button is clicked, the entered task is added to the listbox, and also appended to a text file named "tasklist.txt" for persistent storage.

Functionality for Marking Tasks as Completed: Users can select a task from the listbox and click the "COMPLETED" button to mark it as completed. The completed task is visually distinguished by changing its text color to green.

Functionality for Deleting Tasks: Users can select a task from the listbox and click the "DELETE" button to remove it from the listbox and the text file.

Displaying Tasks in the Listbox: The tasks stored in the "tasklist.txt" file are loaded and displayed in the listbox upon application startup.

Displaying Current Date: The current date is displayed at the top of the window.

GUI Styling: The GUI elements are styled using images and colors to enhance the visual appeal of the application.