More than one display can facilitate your work when you need one screen full of apps and another for more windows and tabs.
Desktop second display: Want a second display for your desktop? Use your laptop. Here's how - The Economic Times
How to Use a Laptop as a Second Monitor - Tech Advisor
Two Laptops Are Better Than One
Laptop Dual Monitors Part 1: 5 Advantages of Having a Second Monitor for Your Laptop
Set up dual monitors on Windows - Microsoft Support
How To Convert Your Laptop Into A Desktop-Like Setup
How to: Dual-monitor setup on a Windows PC
How to Setup Dual Monitors with Laptop or PC
Use a second laptop as a second HDMI screen monitor for your primary laptop (Windows or Mac)