Can you explain what is meant by virtualization and how it is used in modern IT systems?

Virtualization is a technology that allows creating an abstract layer over the physical resources of a computer, such as the processor, memory, storage, or network. This enables running multiple isolated virtual machines (VMs) on a single physical server, each functioning as a separate computer with its own operating system and applications.

In modern IT systems, virtualization is used for:

• Optimizing hardware resource utilization — multiple VMs on one server instead of many physical servers.
• Providing isolation and security — failures or attacks in one VM do not affect others.
• Simplifying management and scaling — quick creation, cloning, and migration of VMs.
• Supporting cloud services and containerization.

Example: a hypervisor (such as VMware ESXi, Hyper-V, KVM) manages virtual machines, allocating the physical server's resources among them.