The open-source Docker virtualization technology is one of the most exciting innovations to enter the enterprise IT space in years. Docker is a container virtualization technology that offers the promise of a more efficient, lightweight approach to application deployment than most organizations are currently implementing. With a traditional virtualization hypervisor like VMware ESX, Microsoft Hyper-V or the open-source Xen and Kernel-based Virtual Machine (KVM) technologies, each virtual machine (VM) needs its own operating system. In contrast, with Docker, applications sit inside a container that resides on a single host operating system, that can serve many containers. Although Docker is a relatively new effort that got under way in March 2013, the project has matured quickly and the Docker 1.0 milestone was released on June 9. Alongside the Docker 1.0 release came the official debut of the Docker Hub, which is a repository for what are known as "dockerized" applications that can be deployed to any Docker host. Some of the world's largest technology vendors, including IBM, Microsoft, Google, Amazon and Red Hat, support Docker. eWEEK examines the world of Docker container virtualization.