Docker is a collection of platform as a service solutions that provide software in packages known as containers by utilising operating system-level virtualization.
There are two levels of service available: free and premium. Docker Engine is the name of the software that is used to host the containers. Docker, Inc. began developing it in 2013 and has been in operation since then.
DockerCon is a free, immersive online experience that includes product demos, breakout learning tracks, panel discussions, hacks & tips, and deep-dive technical sessions from Docker experts, members of the developer community and ecosystem, and industry luminaries. DockerCon is open to the public and is free to attend.