This book chronicles the history of radio as technology and as media. Radio grew from a clumsy, temperamental form of wireless telegraph to a system that is so ubiquitous and easy to use that it has disappeared to users as a technology and became part of the fabric of human existence. This biography charts the growth of the technical end of radio, starting with the history of electricity, and moving through the invention of vacuum tubes, the heterodyne, FM, transistors, and microchips. But the history of radio is not just wires and electricity--it's the story of strange characters, deep thinkers, visionary mystics, hyperactive minds, ambitious souls, power hungry demagogues, and utopian humanists; all of whom strove to make radio into what they thought it should be.