Multiple monitors give you more screen real estate. When you hook multiple monitors up to a computer, you can move your mouse back and forth between them, dragging programs between monitors as if you had an extra-large desktop. That way, rather than Alt+Tabbing and task switching to glance at another window, you can just look over with your eyes and then look back to the program you’re using.
Some examples of use cases for multiple monitors include:
Coders who want to view their code on one display with the other display reserved for documentation. They can just glance over at the documentation and look back at their primary workspace.
Anyone who needs to view something while working. Viewing a web page while writing an email, viewing another document while writing an something, or working with two large spreadsheets and having both visible at once.
People who need to keep an eye on information, whether it’s email or up-to-date statistics, while working.
Gamers who want to see more of the game world, extending the game across multiple displays.
Geeks who just want to watch a video on one screen while doing something else on the other screen.
If you just have a single monitor, you can also use the Snap feature to quickly place multiple Windows applications side by side. But how useful this feature is depends on your monitor’s size and resolution. If you have a large, high-resolution monitor, it will allow you to see a lot. But for many monitors (especially those on laptops), things will seem very cramped. That’s where dual monitors can come in handy.