The "wws800-wws850-hid-bluetooth-with-pin.pdf" document is for pairing a WWS800 or WWS850 via Bluetooth HID to Windows, Mac, or Android using a PIN code. (This scanner model is not known to pair with iOS devices such as iPad and iPhone.) This method should work for all versions of Windows, and is a more reliable method than not using a PIN.
The "wws800-wws850-hid-bluetooth-without-pin-windows-xp.pdf" document is for setting up the WWS800 or WWS850 with a Windows BT adapter in HID mode without a PIN. This will typically only work in Windows XP.
Both documents assume you have our Wasp Bluetooth adapter (note: this is not the same as the WWS800 or WWS850 charging base station). If you are using a different internal or external Bluetooth adapter or device, your experience may vary slightly.