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Windows 10: How to Change Function Key (Fn Key) Behavior
Remember hitting the F5 key to refresh on your Windows 95 computer? It was almost obsessive. Back in the day, the F1-F12 keys each had a single function, but modern keyboards often include additional functions that you can access with an Fn key (also called a function key).
The Fn key turns the F1-F12 keys into dual-function keys. It works like a standard hotkey in principle, but there is one small difference. The combinations vary by manufacturer and model. You’ll find them most often on laptops (where you can usually change things like screen brightness), but you’ll also find them on some specialty keyboards (like gaming or productivity-focused ones).
For example, on a Dell XPS15z you increase the brightness with Fn + F5, while on a Lenovo G560 the same combination brings up the wireless device settings.
