Virtualization level (resource allocation) |
Allocates hardware resources (CPU, RAM, disk, etc.) to virtual machines |
Allocates OS resources (processes, memory, file systems, etc.) to isolated environments |
Guest OS |
Can run multiple, independent operating systems |
Runs isolated environments in a single operating system with a shared kernel and hardware |
Performance |
Higher overhead due to separate operating systems |
Lower overhead (no emulation, shared operating system) |
Security |
Provides strong isolation and security between virtual machines |
Provides process-level isolation, but may not be as secure as hardware virtualization |
Examples |
VMware, KVM, Xen, etc. |
Docker, Linux Containers, OpenVZ, etc. |