Remote sensing in this case is listening to the individual sound a key makes when pressed by the victim, and wear on the keys means that frequently used keys (s

Remote sensing in this case is listening to the individual sound a key makes when pressed by the victim, and wear on the keys means that frequently used keys (such as 'e' or the space bar) would make a slightly different sound than the other keys, as does the hand/finger position used to press a key.