A humanoid android so sophisticated that he was regarded as a sentient life-form with full civil rights.
Data was built around 2336 by the reclusive scientist Noonien Soong at the Omicron Theta colony. Data was actually the second android constructed by Soong; the first was known as Lore. Just prior to the destruction of the colony by the Crystalline Entity, memories from all the colonists were stored in Data's positronic brain for safekeeping. Data was then stored in a dormant condition underground, where he remained until discovered in 2338 by the crew of the Starship Tripoli. Data subsequently joined the Starfleet and eventually became Operations Manager aboard the Enterprise-D.
Data was based on a sophisticated positronic brain developed by Soong, from concepts first postulated in the 20th century by Dr. Isaac Asimov. Data's body closely mimicked humanoid form, and contained approximately 24.6 kilograms of tripolymer composites, 11.8 kilograms of molybdenum-cobalt alloys, and 1.3 kilograms of bioplast sheeting. His upper spinal support was polyalloy, while his skull was composed of cortenide and duranium. Soong went to extraordinary lengths to create a naturalistic human appearance in Data. He gave Data a functional respiration system, although it's purpose was primarily fro thermal regulation (Data was in fact capable of functioning for extened periods in a vacuum). He gave Data a pulse in his circulatory system that distributed biochemical lubricants and regulated microhydraulic power throughout Data's body. Data's hair was even capable of growth at a controllable rates. Data did not require food; he occasionally ingested semi-organic nutrient suspension in a silicon-based liquid medium. Although Data's systems were primarily mechanical, cybernetic, and positronic, sufficent biological components were present to allow him to become infected by the Psi 2000 virus in 2364. While under the influence of the inhibiton-stripping effects of that virus, Data apparently became intimate with Enterprise-D security chief Tasha Yar. Data's basic programming included a strong inhibition against harming living beings, but he nevertheless had the ability to use deadly force to protect others.
Prior to his assignment to the Enterprise-D, Data served aboard the U.S.S. Trieste. During this tour-of-duty, the Trieste once fell through a wormhole. Aboard the Enterprise-D, Data served as Operations Manager, and was in charge of coordinating the many departments aboard the ship. In 2366, Commander Data was seriously injured trying to save Q from an attack by gaseous creatures called the Calamarain. In gratitude, Q gave Data the gift of allowing Data to experience human laughter for a brief time. Data served as father of the bride for the wedding of Miles O'Brien and Keiko Ishikawa in 2367, and found it necessary to learn to dance to fulfill this ceremonial function. Data's first opportunity to command a starship came during the Federation Blockade of 2368. Data was assigned temporary command of the Starship Sutherland in Picard's armada. As an android Data encountered a small amount of prejudice among his human crew, but was nevertheless able to lead effectively. In late 2368, Data traveled back to old San Francisco when bizarre evidence was found suggesting that he had died some 500 years ago. The evidence was Data's severed head, unearthed from beneath the city of San Francisco, where it had been buried for 5 centuries. Back in th year 1893, Data uncovered a plot by aliens from the planet Devidia II who where using the cholera plauge of the time to conceal their murder of humans. While attempting to stop the Devidians, Data's head was severed, and his body was sent forward in time, back to 2368. Aboard the Enterprise-D, Geordi LaForge was successful in reattaching Data's head and body.
Data's attempts to understand human nature once included an effort to learn about the concept of humor, which he studied with the assistance of Guinan and a holodeck-created comedian. Data even tried to grow a beard once, to the considerable amusement of his shipmates. Aboard the Enterprise-D, Data shared his living quarters with a cat that he named Spot. Data tried to provide for Spot's well-being, but found it difficult to predict the cat's prefrences in food. One of Data's more challenging efforts to experience humanity was his attempt to pursue a romantic relationship with Enterprise-D security officer Jenna D'Sora in late 2367. Although D'Sora was attracted to Data, he was unable to return the affection, at least in a manner that she wanted.Data began to experience dreams in 2369 as a result of an accidental plasma shock recieved during an experiment. It was later learned that the shock had triggered a program designed for this purpose by Soong, who had hoped that the program would be activated when Data reached a certain level of development. Data's intial dreams were of Soong as a blacksmith, incongruously forging the wings of a bird, which Data believed represented himself.One of Data's most noteworthy efforts in his quest for humanity was his construction of an android daughter in 2366. Data employed a new positronic matrix transfer technology to allow his own neural pathways to be duplicated in another positronic brain, which he used as the basis for his child. His daughter, whom he named Lal (Hindi for "beloved"), developed at a remarkable rate and showed evidence of growth beyond that of her father, even experiencing emotions. Lal died after having lived little more than two weeks, when she experienced a serious failure in her positronic brain.
Upon remaining to Omicron Theta colony site in 2364, Data participated in the discovery and activation of his android brother, Lore. Physically identical to Data, Lore had radically different personality programming, and attempted to commandeer the Enterprise-D before he was beamed into space. Although Soong was believed to have died at Omicron Theta, he was discovered to have escaped the colony when, in 2367, he remotely gained control of Data, commanding his creation to visit him in his new secret laboratory. There, Soong attempted to install a new chip in Data's positronic brain that would have given Data the ability to experience human emotions. Unfortunately, Lore also responded to Soong's call, and stole the chip from Soong's lab. Dr. Soong died shortly thereafter. Data began to experience emotions in 2369 when his Lore secretly bombarded Data with signals that triggered negative emotions in his positronic brain. Lore used these negative emotions to manipulate Data into joining him and the Borg against the Federation. When Data realized that Lore was manipulating him and harming the Borg, he was forced to deactivate Lore.
The question of Data's sentience, and more specifically whether Data was entitled to full civil rights under the Constitution of the United Federation of Planets, was addressed in a number of important legal decisions. The first, in 2341, was rendered by Starfleet Academy entrance committee that permitted Data to enter the Academy and serve as a member of Starfleet. Several years later, the question was more definitively addressed when Judge Advocate General Phillipa Louvois ruled that Data was indeed a sentient being and therefore entitled to civil rights, including the right to resign from Starfleet if he so choose. As of Stardate 42527, Data had been decorated by Starfleet Command for gallantry and had recieved the Medal of Honor with clusters, the Legion of Honor, and the Star Cross.