Flatpak is a software utility that allows developers to package applications in a way that makes them easy to install and run on various Linux distributions. It creates a sandboxed environment, ensuring that applications run independently from the system libraries, which helps avoid compatibility issues. With Flatpak, users can access a wide range of applications from different sources without worrying about dependencies. This system promotes software distribution and makes it simpler for developers to maintain their applications across different Linux environments, enhancing the overall user experience.