In addition to “Dock Life: Using Docker for All The Things!“, the article that really helped Docker “click” for me was…
Setting Up a Modern PHP Development Environment with Docker
The title says it all; it was exactly what I needed help doing and understanding. The author does a great job of explaining why and how to setup Docker as your replacement for XAMPP/WAMP, Vagrant, et. al.
It isn’t an in-depth understanding of Docker, but it does a great job of covering the bases and getting your hands dirty. Great article!