Win10 landing screen reveals mysterious square icon What?

When you log in to Windows 10 device, you may have noticed the square icon on the keypad or touch screen virtual keyboard. What is this, what is it used for? The answer may surprise you, maybe you already know.

When you type your password, the square icon turns the highlight on the on-screen keypad or virtual touchscreen keyboard on and off. For example, if your PIN is 1234, the icon will not light when you enter these numbers correctly. This square icon is located to the left of the number 0 on the keypad or to the left of the space bar on the touchscreen virtual keyboard. You won't see this option when your device is connected to a physical keyboard.

When you press a virtual button, the square icon on the keypad or touch screen virtual keyboard provides highlight feedback, combined with the button sound, feeling almost as good as pressing the physical button. However, some users may find it more safe to turn off the highlight when entering a PIN or password. We think such an option is good, although many users may not use it.