Docker is one of the most promising technologies these days. It is a container technology based on Linux. A very lightweight form of virtualization. Docker containers can be as small as 50 MB. Much smaller than traditional VMs.
Check out my slides to “Docker Introduction”. I did this talk at the Webmontag in Mannheim. Feedback was very good.
I’m using Docker since beginning of 2014 in production and I love it. It’s a great technology!