X (video game series). X is a science fiction space trading and combat simulator series created by German developer Egosoft. The series is set in the X-Universe where several races populate a number of worlds connected by jumpgates.

Plot 
Hundreds of millions of years before the plot of the X games, the Ancient races, who have transceded their physical form, built billions of jumpgates throughout the universe. Their purpose, as well as their effect, is to limit the development of faster-than-light transportation, creating a reliance on these jumpgates as human and alien species explore the universe. This enables the Ancients to act as shepherds of life, preventing wars between alien species, and monitoring the development of civilisations. 

Unexpectedly for the Ancients, however, mankind would discover jumpgate technology themselves. Over the course of the 21st century, mankind experimented with wormhole technology and successfully built jumpgates in space between Earth and Mars paving the way for the colonization of the solar system and interstellar transport. A jumpgate was shuttled to Alpha Centauri in an attempt to claim a foothold in interstellar space. However, in 2041, unbeknownst to Earth, the Ancients interfered, cutting contact between the humans and their jumpgate, and instead placing one of their jumpgates directly into the Solar System, inviting humanity into the X-Universe. In 2045, humanity began to explore the jumpgate network, finding plenty of suitable planets for terraforming and colonisation. Robotic AI terraformers were sent out into the network to find and terraform planets, but in 2145, corrupted terraformer ships started targetting humanity, killing billions. Earth was saved by the exploits of Nathan Ridley Gunne, who lured the terraformer fleet out of the solar system before the jumpgate was destroyed. Earth was saved, but when the jumpgate was reactivated, it led to a completely different network.

As for humanity on the planets now separated from Earth, they survived, and formed a new civilisation called the Argon, a name coming from the corruption of R Gunne. The Argon gradually lost their cultural connection with Earth, even adopting a new year counting system - NT, for New Time. The Goners, a fringe cult in Argon society, kept archives of "Old Earth" and hoped for an eventual reunion. The Argon first encountered an alien spiecies, the Paranid, in 130 NT. The Boron followed in 323 NT, the Split in 324 NT, and the Teladi in 550 NT. Over the centuries, attacks from terraformers, now known as the Xenon, would occasionally flare up, and the Argon formed the Community of Planets to try and maintain peace between the various alien factions. 

Around 730 NT, at the height of a war with the Xenon, a jumpship from Earth containing Kyle Brennan suddenly appeared in a remote corner of the X-Universe, kicking off the events of X: Beyond the Frontier.

Featured races 
The X-Universe features several sentient species:

 Boron: A squidlike alien race that reveres their queen and love peace. 
 Human: Divided into three factions:
 Argon: Humans who are descended from the remains of the fleet that lured the Terraformers through the gateway that saved Earth in the terraformer wars. The Argon government decided centuries ago that the pain of separation with Earth was best dealt with by changing the official version of history so that humans in the X-Universe believed they evolved in their current location. 
 Goner: Argons who believe the legend of Earth and Nathan R. Gunne (who led the fleet that saved Earth), despite both being officially just a myth.
 Terran: Humans who were born in the Sol system.
 Khaak: A buglike alien race that started war with the Argon in X2: The Threat. They decimated the sector now known as "President's End". 
 Paranid: A three-eyed alien race that hail to their Xaar emperor and have a strict religion. 
 Split: A humanoid tribal alien race that fight within themselves as much as they fight their enemies. 
 Teladi: A reptilian alien race that worship trade and profits. 
 Xenon: A self-replicating artificial intelligence evolved from the terraformers created by the Terrans in an effort to colonise worlds. Now hostile to all life, they destroy anything organic.

The X series 
The series, which was launched in 1999 on the Windows platform, consists of five base games: X: Beyond the Frontier, X2: The Threat, X3: Reunion, X Rebirth and X4: Foundations. The series games are expanded by sequels that both add features and extend the plot. A plot can be undertaken in all games except X-Tension where the player takes part in missions to unfold events.

In 2010, Egosoft released the X-Superbox, a pack containing all the X series games up to that date: X: Beyond the Frontier, X-Tension, X2: The Threat, X3: Reunion, and X3: Terran Conflict. Included in the pack was extra missions within Terran Conflict. Additionally, owners of the pack also obtained X3: Albion Prelude for free when it was released in 2011.

Books 
So far, six tie-in books have been written by , all in German:
 X: Farnhams Legende, 2000, Panini, 
 X2: Nopileos, 2004, Panini, 
 X3: Yoshiko, 2006, Panini, 
 X3: Hüter der Tore, 2009, Panini, 
 X3: Wächter der Erde, 2009, Panini, 
 X Rebirth: Plutarch Rising, 2013, Panini, 

Additionally, two English language novels by were published by Trafford Publishing in 2004 as part of an anthology X-Universe Volume One (): Dominion by Darren "Steel" Astles and Rogue Testament by Steve Miller.

References 

 
Video game franchises
Video game franchises introduced in 1999