The hacker's approach to Special Relativity grew out of an attempt to demystify the puzzling features of the theory to intelligent but intuition-blocked lay persons by a strategy aimed at this particular handicap: The insufficiently understood basic concepts, the most obstinate stumbling blocks, are explained at length first. The four-dimensional cornerstone of the theory, the all-important Invariant, is presented as a geometric structure analogous to the Diagonal of a box-like Frame of Reference to which Time is subsequently added as the Fourth Dimension. The exposition of the theory of...