The status bar displays information when virtual machine is running. Left part of the status bar displays prompt on the menu entry currently pointed by cursor.
Each device (except memory) connected to the virtual machine is presented as an icon on the right of the status bar.
The following devices put their icons onto the status bar:
When a device is involved in the current process,
If a device can be connected/disconnected when running guest OS (CD/DVD-ROM, floppy drive, network adapter, serial and parallel ports, a sound device, and USB), these operations can be executed using the device context menu. Right-click on the device icon to display its context menu and select the command you need. The picture below shows the context menu of the CD/DVD-ROM drive.
For more on this please refer to the Connecting Devices When Running Virtual Machine section.