Reactivation lock is available on selected Samsung devices only (from KitKat 4.4) whereas Factory Reset Protection (FRP) lock is available on some of the Android devices – Samsung as well (from Lollipop 5.1). In case of a reactivation lock you need to have a Samsung account – to enable FRP you just need Google Account. If you change SIM with devices with Reactivation lock, you need to login with your Samsung account – with FRP no login is required when you change SIM. Reactivation lock allows you to trace your device’s location in case it is lost or stolen whereas FRP lock does not have that feature.
When it comes to factory reset, devices with reactivation lock need to have a previously setup Samsung Account in case of unauthorized activity or hard reset. Devices with FRP need Google Account to activate the device in case of any factory reset.