Factory Reset Protection is a security measure built into Android 5.1 and later. It automatically activates when a Google account is added to a device with a secure screen lock. If the device is reset in an "untrusted" way (like through recovery mode), it requires the original Google credentials to be entered before it can be used again, deterring theft.
Introduced by Google, Factory Reset Protection (FRP) is a built-in security feature for Android devices running Lollipop 5.1 and higher. gsmoneinfo androidfrp