Who was Marshall McLuhan, and should we care about him in the 21st century?

¬†“Through the discovery yesterday of the railway, the motor car and the aeroplane, the physical influence of each man, formerly restricted to a few miles, now extends to hundreds of leagues or more. Better still: thanks to the prodigious biological event represented¬† by the discovery of electro-magnetic waves, each individual finds himself henceforth (actively . . . → Read More: Who was Marshall McLuhan, and should we care about him in the 21st century?