Touchpads

How Laptop Touchpads Ignore Your Palm While You Type

Your palm can rest partly on a laptop touchpad while you type, yet the pointer usually stays where it belongs. Then, occasionally, the cursor jumps or a click happens by accident. The touchpad is not simply turning itself off whenever a key is pressed. It is continuously trying to decide which contact is intentional and which contact should be ignored. This process is commonly called palm rejection. It combines information from the touch-sensitive surface with software rules that classify contacts. Understanding that distinction explains both why modern touchpads work surprisingly well and why they can still make mistakes.