HD is hard drive ,HHD is hard DISK drive, It looks like this is a HDD. This will be my 3rd Dell computer the first 2 both had HDD's go bad within a few months so never get the HDD.  SDD only its also faster. You won't get a BIOS Password or Win 10 Key so get the keyfinder exe from Microsoft or you won't be able to repair this Referb - good luck.