The Time MachineFor readers who are new to H. G. Wells, The Time Machine is a good starting point. It's an epic tale about time travel, humanity, and technology in a future world where the human race has split into two sub-races. The time traveler must help to save the weaker, more child-like of the races from the stronger, more animalistic race. Wells also manages to put a great hook on the end of the story by (spoiler alert) having the time traveler suddenly leave his "normal" time to go to who knows what time period.
This geek book recommendation is featured in Jay Garmon's TechRepublic article "The perfect sci-fi library."
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