System.Windows.Forms.SystemInformation is a little known class that exposes a number of static properties that return information about many system settings, such as:

• Icon and cursor size (IconSize and CursorSize properties)
• Height of the menu bar (MenuHeight)
• Number of mouse buttons (MouseButtons)
• Whether the computer is connected to a network (Network)
• Number of monitors on the desktop (MonitorCount)
• How the system was started (BootMode property, that can return FailSave, FailSafeWithNetwork or Normal)

and many others… Refer to the docs for the full list and descriptions. Being all shared/static members, you just write

Dim numMonitors As Integer = SystemInformation.MonitorCount

to know the number of available monitors. As a VB6 programmer you was probably used to call the GetSystemMetrics API function to get some of this information, or used WMI. That’s still possible, but this simple (and little-known) class makes this process much easier, safer, and more immediate.