Calendar Facts

Calendar Facts

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While it may seem like trivia, it (causes huge headaches for software developers / is taken advantage of by high-speed traders / triggered the 2003 Northeast Blackout / has to be corrected for by GPS satellites / is now recognized as a major cause of World War I).

Special 10th anniversary edition of WHAT IF?—revised and annotated with brand-new illustrations and answers to important questions you never thought to ask—out now. Order it here!