This document discusses using Docker to deploy PHP projects. It begins with an overview of some common challenges in deploying PHP projects, like different PHP version requirements across projects. It then introduces Docker and some of its key concepts like containers, images, and layered filesystems. The remainder of the document provides examples of basic Docker commands for pulling images, running containers, and listing containers. The goal is to illustrate how Docker can help isolate environments for different PHP projects and more easily manage varying PHP version requirements.