The technology that uses the concept of "virtual machines" for creating isolated environments is called virtualization. Virtualization allows multiple operating systems to run concurrently on a single physical machine, separating resources and enabling better utilization. Each virtual machine operates with its own operating system and applications, providing a safe environment to test software, run services, or develop applications without interfering with the host system. This technology is widely used in data centers and cloud computing to enhance flexibility and resource management.