They mustn't harm a human being, they must obey human orders, and they must protect their own existence...but only so long as that doesn't violate rules one and two. With these Three Laws of Robotics, humanity embarked on a bold new era of evolution that would open up enormous possibilities, and unforeseen risks.

The Eternals, the ruling class of the Future, had the power of life and death not only over every human being but over the very centuries into which they were born. Past, Present, and Future could be created or destroyed at will. You had to be special to become an Eternal. Andrew Harlan was special. Until he committed the one unforgivable sin - falling in love. Eternals weren’t supposed to have feelings. But Andrew could not deny the sensations that were struggling within him. He knew he could not keep this secret forever. And so he began to plan his escape.

A collection of 20 classic short stories by Isaac Asimov, author of the Foundation series, featuring the definitive and only in-print version of “Nightfall”.

In the 23rd century, pioneers have escaped the crowded earth for life in self-sustaining orbital colonies. One of the colonies, Rotor, has broken away from the solar system to create its own renegade utopia around an unknown red star two light-years from Earth: a star named Nemesis. Now a 15-year-old Rotorian girl has learned of the dire threat that nemesis poses to Earth’s people - but she is prevented from warning them. Soon, she will realize that Nemesis endangers Rotor as well.

Only a few know the terrifying truth - an outcast Earth scientist, a rebellious alien inhabitant of a dying planet, a lunar-born human intuitionist who senses the imminent annihilation of the Sun... They know the truth - but who will listen? They have foreseen the cost of abundant energy - but who will believe?These few beings, human and alien, hold the key to the Earth's survival.

Stephen Hawking not only unraveled some of the universe's greatest mysteries but also believed science plays a critical role in fixing problems here on Earth. Now, as we face immense challenges on our planet - including climate change, the threat of nuclear war, and the development of artificial intelligence - he turns his attention to the most urgent issues facing us. Will humanity survive? Should we colonize space? Does God exist? These are just a few of the questions Hawking addresses in this wide-ranging, passionately argued final book from one of the greatest minds in history.

The millions of people around the world who loved What If? still have questions, and those questions are getting stranger. Thank goodness xkcd creator Randall Munroe is here to help. Planning to ride a fire pole from the Moon back to Earth? The hardest part is sticking the landing. Hoping to cool the atmosphere by opening everyone’s freezer door at the same time? Maybe it’s time for a brief introduction to thermodynamics. Want to know what would happen if you rode a helicopter blade, made a lava lamp out of lava, or jumped on an erupting geyser? Okay, if you insist.

The Battle of Serenity Valley was the turning point that led the Independents to their defeat at the hands of the Alliance. Yet the Browncoats had held the valley for weeks against all odds, before being ordered to lay down their arms. Command stated they refused to send in airpower because the ground war was "too hot". But the soldiers who were there insist that was not true.... While picking up a new cargo on Persephone, Captain Malcolm Reynolds is kidnapped by a bunch of embittered veteran Browncoats who suspect him of sabotaging the Independents during the war.

Long before Casmir Dabrowski and Kim Sato leave their world for the epic adventures of the Star Kingdom series, long before they outwit terrorists and mercenaries and do battle on a galactic scale, long before they become best friends and roommates...they have to meet for the first time. This is that story.

When an experiment to study quantum uncertainty goes spectacularly wrong, physics student Bill Rustad and his friends find that they have accidentally created an inter-dimensional portal. They connect to Outland - an alternate Earth with identical geology, but where humans never evolved. The group races to establish control of the portal before the government, the military, or evildoers can take it away. Then everything changes when the Yellowstone supervolcano erupts in an explosion large enough to destroy civilization and kill half the planet.

The world outside has grown toxic, the view of it limited, talk of it forbidden. The remnants of humanity live underground in a single silo. But there are always those who hope, who dream. These are the dangerous people, the residents who infect others with their optimism. Their punishment is simple. They are given the very thing they want: They are allowed to go outside.

The human soldiers stranded on the planet Paradise have been recruited into an alien legion to do the dirty jobs that the high-tech species won't do. Their first mission is to kick the enemy off a backwater planet no one cares about. It's a simple assignment, except everyone has a hidden agenda, and the planet could become a deathtrap.

For the better part of five decades, Jerry Pournelle's name has been synonymous with hard-hitting science fiction. For the first time, all of Pournelle's best short work has been collected in a single volume. Herein you will find over a dozen short stories, each with a new introduction by editor and longtime Pournelle assistant John F. Carr, as well as essays and remembrances by Pournelle collaborators and admirers.

Over his four-decade career, Sid Meier has produced some of the world's most popular video games, including Sid Meier's Civilization, which has sold more than 51 million units worldwide and accumulated more than one billion hours of play. Sid Meier's Memoir! is the story of an obsessive young computer enthusiast who helped launch a multibillion-dollar industry.

When a high-value scientist is taken hostage inside the galaxy's most dangerous prison, Halek Cain is the only man for the job. The last remaining survivor of the Reaper program, Hal is an unstoppable force of fuel and madness. A veteran amputee-turned-cyborg, he has a history of violence and a talent for killing that is unmatched by any soldier. With the promise of freedom as his only incentive, he'll stop at nothing to earn back his life from the people who made him, imprisoned him, and were too afraid to let him die.