What is the difference between the virtual machine installation ROS and the real machine installation ROS.

The so -called virtual machine installation system means simulating the independent computer environment for various systems. Therefore, the environment is virtual, but the system is real.
Therefore, the system in the virtual machine is the same as the real system and the same function. The only difference is that if the relevant configuration of your virtual machine is incorrect, some real functions will not be realized. For example: If the bridge mode is not adopted, then the virtual network card and the real network card cannot be communicated.
It virtual system depends on the software installed on the real system to achieve functions, so the real system does not turn on, and the virtual system is not running, so it is not to mention the function. But the system installed in the virtual machine will not be lost. When you turn on the virtual software again, then the virtual ROS can still be used. And through reasonable settings, it can be used as another real computer.