The RQ intro post contains information on design decisions and how to use RQ in your projects.
International Space Station notifications with Python and Redis Queue (RQ) shows how to combine the RQ task queue library with Flask to send text message notifications every time a condition is met - in this blog post's case that the ISS is currently flying over your location on Earth.
Asynchronous Tasks with Flask and Redis Queue looks at how to configure RQ to handle long-running tasks in a Flask app.
Flask by Example - Implementing a Redis Task Queue explains how to install and use RQ in a Flask application.
Sending Confirmation Emails with Flask, Redis Queue, and Amazon SES shows how RQ fits into a real-world application that uses many libraries and third party APIs.
Background Tasks in Python using Redis Queue gives a code example for web scraping data from the Goodreads website. Note that the first sentence in the post is not accurate: it's not the Python language that is linear, but instead the way workers in WSGI servers handle a single request at a time by blocking. Nevertheless, the example is a good one for understanding how RQ can execute.