Dual monitor
Dual Monitor or Multi Monitor is a synonym for using multiple computer displays together with one single computer.
Multiple computer displays are positioned next to each other to create a bigger display surface and are connected to a single computer via multiple video adapters or a single video adapter featuring multiple outputs. The computer's operating system merges the individual display screens to a single desktop space – Program windows can then be seamlessly moved across the multiple display screens as if they were all part of one single screen.
Using multiple monitors is a cost-efficient alternative to buying a bigger display as the cost for displays dramatically increase with their size. Besides, the maximum size of computer displays is limited for technical reasons.
Another alternative includes to use a laptop or tablet pc as an additional monitor for another computer by using multi monitor software such as MaxiVista.