The Dock is located at the bottom of the screen by default and the Apple menu bar is located at the top of the screen. You can connect to the external monitor using "Mini-DisplayPort to DVI Adapter" or "Mini-DisplayPort to VGA Adapter". Connect the monitor cable to the Mini-DisplayPort. You can now use the second display to create an extended desktop or mirror primary desktop.
Apple OS X moving the dock & menu bar to second display
To configure multiple monitor click on Settings i.e. "Apple Menu" > "System Preferences" :
Choose "Displays" > Select the "Arrangement" tab:
Make sure you drag the white rectangle (menu bar) to the display on right to move the menu bar to the external display (see fig.02). The display will flickers and may goes black while refreshing the arrangement.