Tab-resize quickly splits Google Chrome into the number of windows you specify.
Once installed, it adds a button to your toolbar which lets you use the extension. Clicking on it gives you several default layouts that you can use.
The extension also supports multiple monitors. You probably already have a way to snap windows through your operating system (Windows can snap left or right, OS X can do splitview in full screen mode, ChromeOS can snap left or right), but this is a quick and easy way to open multiple windows and place them on your screen where you can easily access each window.
I don’t know why it’s called tab-resize since it is actually manipulating the windows.