Flask is a web application framework in Python that provides the developer varieties of choice when developing web applications. It provides tools, libraries, and mechanics that allow you to build a web application with little dependencies or tell you how the project should look like.
Python Flask is good for the web applications that can be a blog website, commercial website, social media website or some web pages. It allows the developers to use some extensions provided by the community that helps to add additional functionality to the web application.
Also, watch this video to create a simple application in Python Flask: