The differences between Docker, containerd, CRI-O and runc Containers run using a complex stack of libraries, runtimes, APIs and standards. The explosion in containers was kicked off by Docker. But soon afterwards, the landscape seemed to explode with tools, standards and acronyms. So what is ‘docker’ really, and what do terms like “CRI” and “OCI” mean? Should you even care? Read on to find out. S