A standalone VM is not connected to any network. You can choose to make a virtual machine standalone and isolated from any network or node, including the host operating system. A standalone VM cannot use any networked resource such as network printers, file or application servers, or shared drives.
Some reasons you might choose to make a VM standalone follow.
Note that if you make a VM standalone, this does not mean that you cannot print from it. You can still set up a local printer connected to a serial or parallel device that is connected to the physical hardware on the host OS. (See the sections "Defining Serial Port Devices" and "Defining Parallel Port Devices" .)
To make a virtual machine standalone, simply do not select any of the choices under Ethernet Adapters when you configure the VM.
Or, you can change a VM to be standalone if you previously configured it with one of the network connection types.