How does a container differ from a virtual machine? What are the advantages?

A container and a virtual machine (VM) are isolation technologies, but they work differently:

• A virtual machine emulates a complete hardware environment, including its own OS. A hypervisor runs on the host and creates VMs with separate OS.
• A container isolates processes at the OS level, using kernel features (namespaces, cgroups), with all containers sharing the same kernel and host OS.

Advantages of containers:

• Lightweight: containers use fewer resources and start faster.
• Portable: containers include the application and its dependencies, simplifying transfer.
• Scalable: quick deployment and management of many instances.

VMS provide stronger isolation and can run different OSes, which is useful for testing or running incompatible environments.

Example: Docker is a popular containerization tool, while VMware or KVM are used for virtualization.