Free modules are an excellent way to enhance the functionality of a Joomla 4 based website without incurring additional costs. There are various types of free modules available that allow you to add new features such as: displaying recently added articles, displaying popular content, sharing content on social media, etc. It's important to remember that just because modules are free, it doesn't mean that they are of lower quality than paid ones. Many of them are just as well-designed and just as effective, so it's important to review options and user reviews before installing. If you are interested in finding free modules for your Joomla 4 website, I recommend checking out the official Joomla Extension Directory (JED), where you will find thousands of free extensions to choose from.