Containerization is not new anymore. IT organizations worldwide have started venturing into the cloud-native space where containerization is at the heart of application infrastructure. Developers and Operations teams looking for agility and efficiency in application development and delivery have started focusing on cloud-native application architectures that enable the portability of applications between different platforms and cloud providers. The first step when you venture into this new world of application development is to understand containerization. Docker, the company, brought containerization to the masses. Docker made it easy to package, distribute, and deploy your application code in a platform-agnostic way. The tools that Docker introduced abstracted all complexity in running multiple applications as isolated processes on the same host. Docker also identified an opportunity to develop standards around containerization to avoid technology fragmentation. This standardization through Open Container Initiative (OCI) brought many innovations in application packaging, delivery, and deployment. This also enabled several other vendors to come up with innovative solutions for customers to choose from. As a customer or an IT administrator or an architect or a developer, you have a choice of vendor. Kubernetes too, through the Container Runtime Interface (CRI), provides a way to use a container runtime of your choice.

Before you jump into making this decision, you must the features offered by these different runtimes and limitations if any. It is also important to understand the technology or the constructs behind containerization to make these decisions. This book is exactly for that. This book starts with why containerization and proceeds towards explaining the constructs that are used to create isolated application processes -- what we call containers. This book, then, ventures into Docker and Podman container engine concepts. Toward the end, you will learn how Kubernetes can help you manage containers at scale and why it is important to learn Kubernetes.

Overall, this book takes you from a novice to a be an expert in containerization.