Flask is a popular Python framework for developing web applications. Classified as a microframework, it comes with minimal built-in components and requirements, making it easy to get started and flexible to use. At the same time, Flask is by no means limited in its ability to produce a fully featured app. Rather, it is designed to be easily extensible, and the developer has the liberty to choose which tools and libraries they want to utilize. As such, Flask is capable of creating both simple static websites as well as more complex apps that involve database integration, accounts and authentication, and more!

In this lesson, we’ll start by looking at an example of a minimal Flask application. It will display the text, Hello, World! on the webpage. You’ll learn how to create this and build on top of it in the following exercises.

Let’s get started!


Click Run to start the app. Feel free to take a look at the code in app.py and move on when you’re ready!

Notice that the app is being run in http://localhost:5000/ on the embedded browser. For now, this app is just running locally and can only be accessed there.

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