Virtualization has been the main mechanism for hugely optimizing and organizing various IT infrastructures (server machines, storage appliances, networking, and security solutions). The proven divide and conquer technique accomplished through VMs is the main target for IT optimization. In the recent past, Docker containers emerged as a blessing in disguise. Containers contain only what is necessary to build, ship, and run software applications. Unlike VMs, there is no guest OS or hypervisor necessary for containers. This allows enterprises to radically reduce the amount of storage and totally eliminate hypervisor licensing costs. The number of containers that can be accommodated in a physical host or in a VM is more compared to the number of VMs being stuffed in a physical machine. This means that containers are fine-grained whereas VMs are coarse-grained. The wastage of resources is very minimal in the case of containerization. Every bit of IT infrastructures and resources is being methodically used by containers.

Portability is another factor. This enables IT operations teams to move workloads across different cloud services, physical servers, or VMs without locking them into using a specific infrastructure tooling. Workload consolidation or optimization through containers is error-free because containers can run everywhere. In the case of VMs, VM placement is a tricky and tough affair considering the diversity of hypervisors / Virtual Machine Monitors (VMMs). The point here is that Docker allows enterprises to optimize infrastructure utilization and decrease the cost of maintaining existing applications, which is incidentally the number one challenge enterprise IT teams face every day.

Docker greatly reduces the amount of time it takes to install an application, scale to meet customer demands, or simply start new containers. This means, taking new offerings to market is exceedingly fast because the underlying infrastructure (virtual or physical) is being readied in a few seconds.