Flask is a lightweight WSGI web application framework. It is designed to make getting started quick and easy, with the ability to scale up to complex applications. It began as a simple wrapper around Werkzeug and Jinja and has become one of the most popular Python web application frameworks.

What is flask used for?

Flask is a web framework. This means flask provides you with tools, libraries and technologies that allow you to build a web application. This web application can be some web pages, a blog, a wiki or go as big as a web-based calendar application or a commercial website.

Is flask a frontend or backend?

In web development, there is only one “front end” language, and that’s JavaScript (and things compiled to JavaScript, like TypeScript). Everything else runs on a server somewhere, not in the browser, and that makes it “back end”. Flask, which is written in Python, is back end.