I know that we have a sense that allows the brain to keep track of the locations of each of our limbs, digits, etcetera, but I can never remember what it is called. I would guess that most people aren't aware that this sense even exists, although life would be very difficult without it (you know how hard it is to walk when you have a "dead [i.e., numb] leg"? Imagine that, in all your limbs, all the time).
What is the technical term for this sense?