Section 1: An Introduction to Docker – Containers and Local Development

In this section, we introduce the reader to the technologies, skills, and steps involved in developing applications using Docker Containers. We begin by tracing the history of hosting and why we need Docker in the first place. We then demonstrate the differences between virtualization and containerization, using VirtualBox to create simple virtual machines and using Docker to create a simple PHP application with state. We discuss how applications involving multiple containers working together (microservices) are the ultimate way to use containers, and present a simple CRUD demo involving several containers, including some prepared by third parties and shared with us on Docker Hub. Finally, we present the Docker Compose tool as a means to orchestrate complete applications made up of multiple containers, while providing private access between the containers.

This section comprises the following chapters:

• Chapter 1, Introduction to Docker
• Chapter 2, Using VirtualBox and Docker Containers for Development
• Chapter 3, Sharing Containers Using Docker Hub
• Chapter 4, Composing Systems Using Containers