Bronze Age
Victor Stone first appeared as a member of the New Teen Titans, when the mystic Raven gathered together a trio of members of the original Titans, and group of new, young recruits, of which Vic was one. By the time Raven found him, 18 year old Victor Stone had already undergone a horrible tragedy that changed his life forever. A star athlete, Vic had already cast aside any aspirations his parents might have had for him becoming a scientist like they were. Instead, he focused on training to be an Olympic level athlete.
But one day, upon a chance visit to his parent’s lab, he came upon disaster. During an experiment conducted by his mother and father, they had unleashed a deadly creature from another dimension. The creature instantly killed Victor’s mother, and then destroyed much of Vic’s own body. Victor’s father Silas, crippled with guilt about what his experiment had unleashed, chose to save his nearly dead son by giving him enhanced cybernetic upgrades. These upgrades left most of his body, including half his face, encased in molybdenum steel. Cybernetic parts were grafted to Vic’s organs, and computerized synthetic nerve bases were attached to his spinal column. When he finally woke up from the various procedures it took to make Vic a cyborg, he was horrified at what he had become, thinking himself a freak, and a version of Frankenstein’s monster. And he loathed his father for not allowing him to simply die.
Now unable to pursue his sports dreams due to his huge advantage over regular athletes, he lost most of his friends and lived a lonely existence, seeing his father (and most other people) as little as possible. But when Raven inducted him into the Titans, he found a family again, and a purpose. He instantly bonded with Gar Logan, better known as Beast Boy, and the pair began a older brother/younger brother relationship. Vic, now dubbed Cyborg, eventually mended fences with his father before he died, and reconnected with his grandparents, who were former jazz musicians. During this time, he even started dating a woman named Sarah Simms, who was an instructor for a group of disabled children, many who had prosthetic limbs. To those kids, who saw a bit of themselves in Victor, Cyborg became a hero even bigger than Superman.
Modern Age
In an accident during the "Titans Hunt" storyline, Cyborg was heavily damaged in battle, and was left in a catatonic state, with no traces of his original brain activity left. He only responded to computer commands, leaving him a shell of a human being. His friends on the team never gave up on him though, and eventually, his mind was restored by an alien race of computer intelligences called the Technis. Although his mind was restored, Vic had to remain with the Technis both to maintain his identity, and also because in exchange for restoring him, he had promised to teach the Technis about humanity. Now called Cyberion, he was now a complete part of this alien technological collective.
In time, Cyberion returned to Earth, his consciousness now totally sublimated into the Technis collective. Due to an innate feeling of loneliness, he began to gather his former Titan friends, kidnapping them and giving them idyllic lives in a sort of fantasy simulation, in order to keep him company. But the Titans were able to break free, and reach the part of Cyberion that was still their friend Victor Stone.
Vic then "downloaded" his freed consciousness into the Omegadrome, a morphing war-suit belonging to an alien former Teen Titan named Minion. After being freed from Technis, the Titans reformed and Vic was part of this new iteration of the team. Nightwing revealed that he had cloned Victor’s original body, and the Omegadrome, which carried his mind, fused with his cloned body, allowing him to look human when he wanted, while still wield amazing technical powers. During an adventure with the Flash, his morphing abilities were lost, and once again he found himself the permanent half human/half machine Cyborg.
Eventually, a new version of the Teen Titans was formed, made up mostly of former members of the team Young Justice. For a time, Cyborg served as their mentor, along with other former Titans who were now adults. Eventually, Victor Stone was finally accepted as a member of the Justice League of America, having officially graduated into the most prominent Super-Hero team of them all.
New 52
In the wake of 2011's FLASHPOINT, the DC Universe timeline was heavily altered. In this new reality, Victor Stone was never a member of the Teen Titans, but was instead a founding member of the Justice League. In this timeline, much like the previous one, Vic was a genius, one who only wanted to play professional sports and who set aside academics. While visiting his scientist father at S.T.A.R. Labs, he found Dr. Stone tinkering with an Apokoliptian Mother Box of immense power.
In the middle of an argument regarding Vic’s future, the Mother Box, which is a sentient computer system, opened a portal to the planet Apokolips called a Boom Tube. As the Parademon minions of Darkseid swarmed into the lab, Vic was struck by a burst of energy, which nearly killed him and destroyed most of his body.
Vic’s father Silas used all his scientific knowledge to build his son a new cyborg body, but he also fused it with alien Mother Box technology. This upgrade allowed Vic to “hear” other computer systems, and even open his own Boom Tubes. Joining with heroes like Superman, Batman and Wonder Woman, Victor became a founding member of the Justice League, although he was much younger and less experienced than his teammates. His ability to create Boom Tubes was very useful whenever the League needed to transport to any location in the world in the blink of an eye. Cyborg has since proven an invaluable member of the League.