Our CTO Trent has written a detailed overview about why Docker is the future of WordPress, which you can find here. Below are some parts of his article to quickly outline the many benefits.
Most web hosts use virtual servers. They’re slow, resource intensive, barely scalable, and have so many layers it is easy for something to go wrong. If anything goes wrong in just one of those tech layers your website goes down.
So what are Docker containers? Docker containers are a piece of software that wraps around code, system tools, system libraries, and anything else you can install on a server. Using docker containers you can essentially run WordPress like an operating system, and deploy it like an application.
Better yet, containers make WordPress more scalable, and more efficient bringing down the economies of scale per install. What this effectively means is that we can host more WordPress installs with less server and management resources bringing down the cost per install, while also improving performance by building an isolated environment (container) completely dedicated to serving a high-performance, scalable WordPress site.