One reader of my previous knol “Newton’s Laws, The Concepts,” suggested that I extend the presentation to illuminate the laws of mechanics according to Einstein. Although this is a challenge, Relativity also has its elegant logic which can be be explained without impenetrable mathematics, and without the need for sending cryptic signals from a train to conspirators on the ground, the way most Relativity explanations start. That may have been appropriate in Einstein’s time, at the beginning of the 20th century, but in 21st century security guards might find it suspicious