How is a container different from a virtual machine?

A container packages an application and its dependencies while using an operating-system kernel through isolation mechanisms. A virtual machine runs a guest operating system on virtualized hardware. Containers often start quickly and share more host resources, but that does not make them a complete security boundary in every environment. Images, runtime privileges, kernel exposure, and host configuration matter. VMs usually provide a distinct guest-kernel boundary at additional overhead. Choose according to isolation, compatibility, management, and workload needs rather than assuming one replaces the other everywhere.