What is the difference between Docker containerization and full virtualization using virtual machines?

Docker containerization and virtualization with virtual machines (VMs) differ in the level of isolation and resource usage:

• Virtual Machines run a full guest OS on top of a hypervisor. Each VM contains its own kernel and system libraries, which requires significant resources (CPU, memory, disk).
• Docker containers share the host OS kernel and isolate applications at the process and filesystem level. This allows containers to start faster and use fewer resources.

Example:

• VM: a separate OS, such as Ubuntu, runs on a Windows host.
• Docker: a container with an application runs, using the host kernel without a separate OS.

Thus, Docker provides a more lightweight and faster application isolation, but with a lower degree of isolation compared to VMs.