How do containers work - what is OverlayFS?

The article by Jen Wike Huger delves into how containers work, particularly focusing on OverlayFS. OverlayFS is a file system that allows the combination of two file systems into one, which is fundamental for container operations. The article breaks down the essential components of OverlayFS, such as its structure and operational methods. It explains how OverlayFS allows for overwriting files without altering the original data, a key aspect of creating and managing containers. The author also provides examples of its applications and benefits within the realms of virtualization and containerization. The discussed examples illustrate how OverlayFS enhances the efficiency and flexibility of container-based systems, making it a very useful solution in modern software development.