Docker container has much more potential than virtual machines. Docker containers can share a single kernel and share application libraries. This doenot have any hardware isolation unlike standard virtualization. Virtual machines are slower as compared to docker. A virtual machine may take several minutes to create and launch.
Companies are adopting docker container at an affordable price. It is widely adopted. Instead of virtualizing hardware, these rest on top of a single Linux instance. With a perfectly tuned container system, you can have as many as number of applications.