By request of Paradox to keep this thread going I have compilled facts for it.
The Original Team
First Appearance: Brave & The Bold #54 [un-official]; Brave & The Bold #60 [official]
Robin, Kid Flash and Aqualad joined together to stop the menace of Mr. Twister in Hatton Corners. It was the first time the sidekicks joined forces.
Their second meeting was more eventful: Robin, Kid Flash, Aqualad, now joined by Wonder Girl and Speedy, fought against their mentors, who had been possessed by the evil Antithesis. At this second meeting, the five youngsters decided to become a team... and the Teen Titans were born! Robin naturally became the leader of the original Teen Titans.
The sidekicks would continue to operate with their mentors, as well as spending time with their peers in the Teen Titans. [Donna Troy herself suggested the name Teen Titans - based on residual memories from her childhood on New Chronus.] Speedy elected for part-time membership, and the remaining four became the core team.
THE TEEN TITANS: PRE-CRISIS
During this time, the foursome established a headquarters called the Titans Lair, and responded to teenagers needing help. The team encountered various threats, including the Mad Mod and the Gargoyle.
Soon, responsibilities in Atlantis forced Aqualad to take leave from the team, and Speedy stepped in as a full time member.
Mr. Jupiter and a New Direction
Following a series of successful adventures, the youths were involved in a tragedy that would alter their course. At a peace rally, a riot broke out and the Titans, in their civilian identities, tried to stop the violence. Instead, they accidentally brought about the death of the keynote speaker. Dr Arthur Swenson. Shaken, the group plus Hawk and Dove, gave up their costumed identities for a time. It was at the urging of financier Loren Jupiter that Kid Flash, Speedy, Wonder Girl, Hawk and Dove joined his program of training teens to utilize their potentials; Also joining the program was the mysterious Lilith and Mal Duncan.
Robin eventually solved the Swensen case and the Titans were cleared of the murder. They returned to their costumed identities, and Hawk and Dove left the group. Now rejoined by Robin, the Teen Titans continued their adventures. The group later disbanded after helping an old man rid his estate of a demonic race of creatures.
The Team Reforms
The second version of the Teen Titans came into being after the young heroes defeated Dr. Light, who had summoned them all to Titans' Lair in his attempt to get revenge on the JLA by attacking their young companions. All of the original Titan members eventually returned, plus new recruits such as the Bumblebee and the Herald [Mal Duncan]. Many other young heroes crossed paths with the Titans, including a west coast group of Teen Titans formed by Lilith. After a while, the Titans realized that they had their own lives to lead, and the group disbanded.
Titans West was officially formed by Lilith during the second version of the Original Teen Titans. Mr. Esper, a mysterious foe, used his Mental Helmet to tap into Lilith's mind and then caused disasters on both the East and West Coasts. He later used her powers to create his second identity, that of Captain Calamity. Lilith realized that she was the cause of all these "calamities" and formed Titans West after successfully dealing with Mr. Esper's plan to separate Long Island from the U.S. in order to form his own nation.
Titans West consisted of Hawk, Dove, Lilith, Golden Eagle, Flamebird and Beast Boy. The group did not have a headquarters, nor much of any official structure. After being rebuffed by Robin, Hawk decided that he himself would lead Titans West. The group folded soon afterward, due to Hawk's inability as leader.
New Teen Titans
First appearence: DC comics presents #26
Raven Gathers the New Teen Titans
Upon the strange arrival of Raven at the homes of Robin Kid Flash and Wonder Girl, the group was reunited. She called the group together to repel an attack by the Gordanians, who were trying to recapture Starfire, a princess from Tamaran. Also joining the group was Vic Stone, a cyborg, and Beast Boy (now using the name Changeling).
Flush with success, the group decided to remain as the New Teen Titans. After a handful of missions, it became apparent that Raven brought the group together to be readied for an attack by Trigon, Raven's father and the demonic ruler of another dimension. After narrowly defeating Trigon, the group remained together and had a successful career.
The New Teen Titans amassed quite an array of adversaries, including the H.I.V.E., The Ravager, Deathstroke the Terminator, the Fearsome Five, the new Brotherhood of Evil, Brother Blood and Starfire's sister, Blackfire.
There have been numerous mishaps and tragedies along the way such as when the group was infiltrated by Terra, a super-heroine who was actually working for the Terminator. Mentally unbalanced, Terra seemingly brought about her own death although the act deeply shocked Changeling, who thought he loved her. Robin, at that time, chose to forge a new identity for himself and became Nightwing, remaining the team's leader. It was during that adventure that the Titans met Joseph Wilson (son of the Terminator), who had the ability to possess other people. Adopting the name Jericho, he worked alongside the Titans for a time before becoming a full-fledged member.
The group had cases that took place not only around the world but to other planets and dimension. Joining them on various adventures were former members and new allies, including Lilith, Aqualad, Aquagirl, the crystal spinner Kole and mysterious winged man, Azrael.
The Titans assisted various heroes in the Crisis on Infinite Earths; the Crisis claims the lives of Titans allies, Aquagirl and Kole. Following the Crisis, Wally West assumes the role of his fallen mentor and became the Flash.
Soon after, the team fell on hard times: Starfire was forced to return home to Tamaran for an arranged marriage; Wonder Girl tried to hold the team together but failed: upon returning to Earth, Nightwing went on a hunt for Raven (who had disappeared months earlier after another confrontation with Trigon), and fell into the hands of the Titans' deadliest enemy, Brother Blood.
Starfire returned to Earth, forsaking her husband, and has rejoined the group which managed to pull itself back together with the help of some of the original Titans (Aqualad, Speedy, Hawk, Robin II and Flash). Together, the rejoined Titans team and a group of allies defeated Brother Blood and rescued Nightwing and Raven. Following these events, the Titans reestablished themselves with Nightwing as leader.
Adrian Chase's nephew Danny, a telekinetic, was admitted to the team after helping them defeat the mercenary Godiva. [Danny is later asked to leave the Titans by Nightwing, who will not take responsibility for someone so young on the team.]
After Wonder Girl and the rest of the Titans went to New Chronus to learn Donna Troy's true past, they dropped the "Teen" part of their name and began calling themselves the New Titans.
First Appearance: New Titans #50
After Wonder Girl and the rest of the Titans went to New Chronus to learn Donna Troy's true past, they dropped the "Teen" part of their name and began calling themselves the New Titans. Soon after, Titans members were hunted and captured by the mysterious Wildebeest Society. Nightwing avoided capture and soon learned the dark secrets of the organization's origins…
Some months ago, the corrupted souls of Azarath regained their strength and merged with Jericho. The souls now needed powerful vessels for each of them to survive. Now possessed by this force, Jericho sought to acquire superhuman beings as vessels for the souls of Azarath. Jericho found a unique opportunity: He invaded and took over the Wildebeest Society (which was a petty group of villains made up of former HIVE operatives). Using them as a front, he abducted current and former Titans to act as vessels for the souls of Azarath.
The remaining Titans Nightwing and Troia (along with new allies Arella, Phantasm, Pantha, Red Star and Deathstroke) found the Wildebeest lair and ultimately destroyed the Wildebeest Society. This event is catalogued as "Titans Hunt."
During the Titans Hunt, Golden Eagle is slain, Cyborg is nearly destroyed, Titans Tower is demolished, and Phantasm is revealed to be Danny Chase, who is himself slain along with Raven's mother Arella as the Titans defeat the Wildebeests. Raven is transformed utterly and disappears. Also, in order to defeat the society, Deathstroke was forced to slay his own son, Jericho.
The Titans were joined by new members: the violent Pantha, former ally Red Star, the mysteriously re-formed Phantasm (now an amalgam of Danny Chase, Arella and the souls of Azarath), and Baby Wildebeest (a leftover genetic experiment from the Wildebeest Society).
ARSENAL'S TITANS TEAM
Soon, a group called the Team Titans emerged, claiming to be from the future. The Team Titans mission: Kill Donna Troy before she can give birth to the man who, in their future, would become the evil Lord Chaos. Lord Chaos also emerged, determined to ensure his own future. Troia eventually gave birth, and with the help of the New Titans and the Team Titans, she saved her son Robert while defeating Lord Chaos. The Titans of myth helped in the ensuing battle as well. Ultimately, Donna Troy decided to give up her Troia identity, and become a normal human. The Titans of myth granted this wish, and left Donna Troy powerless. Donna Troy and the Team Titans relocated to a farm in New Jersey.
Endings and New Beginnings
Meanwhile, Dick Grayson [Nightwing] proposed marriage to Starfire. The two almost wed, but the ceremony was interrupted by the dark incarnation of their former team mate, Raven. Her brutal attack on Starfire triggered changes in Dick and Kory's relationship. Starfire is implanted with a Raven "seed" which causes her to leave Earth and go on a spiritual journey. The two grew apart, and Starfire eventually returned to her home planet of Tamaran.
At the same time, the Titans were pressured to place themselves under the government's watchful eye, due to increased public scrutiny. Sarge Steel was their chief liaison, and Nightwing stepped down as leader and allowed Arsenal to take command. Arsenal led this new group of Titans, and was consistently challenged by the burdens of leadership. Many members left, but new faces emerged as well. Arsenal's team consisted of Darkstar (Donna Troy), Green Lantern, Supergirl, Damage, Mirage, Terra II, Minion, Impulse and Rose Wilson. Eventually, each members' dedication to the team began to waver, and the team disbanded.
The Team Titans' story began 10 years in the future; Or, rather, the false future where Lord Chaos reigned and a force known as the Team Titans struggled to overthrow his tyranny.
To combat the Titan-god, the mysterious Team Titans leader sought out or created groups of super-powered teens. Collecting these youths together as the Teen Titans, named in honor of the original super-hero group of the 20th century, he created a nearly invisible army of underground freedom fighters. But he knew Lord Chaos's power, and he knew if Chaos had captured any one of his warriors, they could be forced to reveal his location and the whereabouts of the entire Teen Titans army. To prevent this, he created smaller subgroups of Titans. Each small platoon force was given specific missions, but knew nothing of their leader or the whereabouts of the other Titan-platoons. This would assure each group's safety, as well as the safety and existence of the entire underground.
A man named Lyons (whose family was slain by Lord Chaos) vowed revenge on Chaos and joined the rebellion. Lyons, now dubbed Battalion, became the ‘drill sergeant from hell' to the Team Titans. He worked with the future-Nightwing in training these young warriors.
Back to the Past
Shortly thereafter, the Team Titans leader gave the team a mission: travel 10 years into the past to stop Chaos from ever being born. To accomplish this, the Teamers were assigned to kill Donna Troy before she would give birth to the child who would become Lord Chaos! The Teamers successfully traveled to the past and came into conflict with the Titans.
Donna gave birth to her son before the Teamers could intervene. However, the Titans and the Team Titans were able to stop Chaos and spare Donna's life at the same time. After this, the Teamers found themselves stranded in the past, unable to return to their future. With nowhere else to go, they resided at Donna Troy's New Jersey farmhouse.
The Teamers tried to find a place in this new world. Also joining them was Battalion, who had traveled to the past as well.
Shortly after that, the future version of Nightwing entered this timeline. Mirage was reunited with her lover only briefly. A dark version of Raven attacked the future Nightwing and corrupted him by planting a Trigon-seed within him. Nightwing now renamed himself Deathwing, and became violent and brutal. Deathwing visited Mirage, where he attacked and raped her. Mirage then learned she was pregnant with Deathwing's child.
The Team Titans encountered new threats from present day as well as their own future timeline. Some Team Titans were allies (the female rock group Metallik) while others were adversaries (Judge and Jury). The Teamers also encountered the power-mad Titan, Lazarium, whose schemes led the Teamers to encounter dozens of time-tossed Team Titans.
Shortly after this, the Teamers lives were disrupted by the time crisis known as Zero Hour. It was revealed that the Team Titans leader in the future was the villainous Monarch! He created that false future world so he could train meta-humans (The Team Titans) to act as sleeper agent assassins. He brought various super-powered beings from alternate realities and trained them as Team Titans. He knew of the impending time crisis, and wanted a super-powered army at his command. Extant (the time villain that Monarch had transformed into) commanded all the Team Titans to attack the heroes who were trying to unravel this time crisis. Extant sought to use the time disruption to his advantage. His plan was thwarted; the heroes contained the Teamers. Time continued to collapse, erasing the false timelines that had emerged. As a result, all the Team Titans were erased from existence!
Strangely enough, three people remained unscathed from Monarch's false timeline: Tara Markov (Terra II), Miriam Delgado (Mirage) and Deathwing (who was believed to be a future Dick Grayson). Terra and Mirage remained members of a new Titans team, led by Arsenal (Roy Harper). Shortly after the team was reformed, a strange orb appeared, with messages for Mirage and Terra.
The orb was sent by the Time Trapper. The Time Trapper revealed that Mirage, Deathwing and Terra were from this timeline, NOT an alternate timeline, as they had thought. That is why they survived the time crisis. Mirage was a runaway street urchin from Brazil. The Time Trapper kidnapped her and implanted false memories in her brain; she believed she grew up in Monarch's false timeline.The Trapper became aware of Extant's petty manipulations of time, and set up his own sleeper agents (Terra, Mirage and Deathwing) that would be able to fight Extant's programming. The Time Trapper also revealed that Terra was from this timeline as well.
Teen Titans II
First Appearance: Teen Titans [second series] #1
preview featured in Superman [second series] #116
Isiah Crockett (who would later become Joto), Toni Monetti (who would later become Argent) and Cody Driscoll (who would later become Risk) are all abducted by the alien race, H'San Natall. Just before Crockett was abducted, the Atom was caught in the energy stream and was transported as well. Once on the alien ship, they meet and rescue another earth girl (who would later become Prysm) who was raised in a virtual reality environment that mimics life on earth (based on old TV shows from the 50's). The group of teenagers is able to escape the aliens and return to earth.
During the adventure, the teens learned that they were half-alien, and their mothers were impregnated by the H'San Natall. They discover they were all born on June 21st. Apparently, the kids were part of a sleeper agent program by the H'San Natall to defeat the super-powered beings already on Earth. The group stayed together, and with the funding of Loren Jupiter, became the latest incarnation of the Teen Titans. Atom decided to remain on the team to learn how to readjust to his life as a teenager (since he was de-aged by Extant during the Zero Hour Crisis).
Next, the Teen Titans embarked on a series of adventures. They battled Dark Nemesis and the xenophobic Pylon, and joined forces with Travis Morgan, the Warlord, in Skartaris. They also meet Fringe, another H'San Natall-created Titan, and Prysm becomes his protector.
Jupiter was later forced to gather together the original Titans – Nightwing, Tempest, Flash and Arsenal – to combat the threat of his bitter, super-powered son Jarrod Jupiter (Haze). New and old Titans joined forces to defeat Haze – but at a price; Joto seemingly lost his life and Arsenal felt responsible for his death. Arsenal remained with this new group of Titans for a time, but eventually left the group before it disbanded. During this battle, the mysterious Omen was revealed to be former Titans, Lilith.
The Teen Titans almost disbanded following these events, but Argent rallied the team to re-form. After a recruitment drive, Captain Marvel, Jr. and Fringe joined the team.
After a confrontation with Deathstroke, the teens were taken to Titan, the moon of Saturn, where they confronted their H'San Natall creators and Prysm's mother. Joto was resurrected, and Prysm and Fringe decided to remain on Titan. Upon returning to earth, the Titans learned that Atom has been restored to his true age. The rest of the team decided to go their separate ways and disbanded.
First Appearance: JLA/Titans #1-3 [unofficial]; Titans #1 and Titans Secret Files #1 [official]
Old Friends and New Beginnings
Having collected a planet-size assortment of technological debris, Cyberion journeyed to Earth to turn its moon into a new Technis world and populate it with his Titans allies. The JLA and the Titans first clashed, then united, to prevent Cyberion from destroying the planet while saving Vic's soul and downloading it into Minion's morphing battlesuit, the Omegadrome.
The original five Titans then decided to re-form the team. Joining the five originals were Starfire, Cyborg, Damage, Argent and Jesse Quick. The Titans encountered new adversaries, including the demonic Goth, newly reformed H.I.V.E., and Vandal Savage's anti-Titans group called Tartarus.
Various missions and circumstances led team members to leave the Titans. Starfire decided to stay of the world of Karna to help rebuild the Tamaranian culture; Damage left the team to do some soul searching and finally deal with the emotional scars of his abuse as a child; Cyborg was granted a new human cloned body and embarked on a new life; the Flash stepped down in an effort to cajole Jesse Quick to resume her membership in the team.
The Titans Tower soon became overcrowded with members and non-members alike; In addition to Titans members, the Tower was populated with Lian Harper, Dolphin, Cerdian, Rose Wilson, five kids who escaped from a DEO orphanage, and a mysterious youth known as Epsilon. Epsilon was eventually revealed to be under possession by a DEO orphan named Kevin. When the real psychotic Epsilon emerged, he cut a swath of destruction that resulted in the utter destruction of the Titans Tower. Eventually, Epsilon was defeated and the DEO orphans were provided better care with the DEO.
Shortly afterward, A mysterious conglomerate known as Optitron offered to sponsor the Titans and Young Justice after summoning them to San Francisco. Before any decisions could be made, a mysterious cybernetic girl [known as Indigo] from the future invaded the complex - and immediately engaged combat with both teams. With half the team out of commission, the remaining members tried to track down Indigo, but instead encountered a rogue Superman android which had been activated. Caught by surprise, Lilith has her neck snapped by the Superman android, killing her instantly.
Troia tried valiantly to defeat the Superman Android, but he released a deadly heat beam directly through her chest, killing her. Indigo arrived and shut down the Superman Android, leaving Arsenal and Nightwing to mourn the fallen Troia.
At Troia's funeral, Nightwing declared to Arsenal that he is tired as seeing friends die and the Titans are officially over. Meanwhile, members of Young Justice, especially Wonder Girl, felt responsible for the tragic deaths. This led Wonder Girl, Robin, Impulse and Superboy to form a new group of Teen Titans under the guidance of the more experienced Cyborg, Starfire and Beast Boy.
First Appearance: Titans Secret Files #2
When the Titans team recently reformed, Gar Logan (Changeling/Beast Boy) elected to waive membership and resume his acting career. His life so far in Hollywood has been less than stellar. Work isn't coming as easily as he'd hoped, and he's already made a few enemies. In Hollywood, it seemed that everyone recognized Gar Logan by his old code-name, Beast Boy. Since then, Gar has gone back to that code-name, whether he likes it or not! Gar was also framed for murder by Gemini, the daughter of Madame Rouge. Gar was cleared with the help of Nightwing and Flamebird.
Recently, Gar's obnoxious cousin Matt took it upon himself to hold a membership drive party for an all-new Titans West. Although the party was crashed by a jealous Duela Dent and vengeful Fear & Loathing, a few potential members remained. Gar finally agreed to have the team re-form, and Titans West was re-dubbed Titans L.A. - with members that included Beast Boy, Flamebird, Herald, Bumblebee, Terra, Hero Cruz, Captain Marvel Jr. and Bushido.
But Titans LA was short-lived; When visiting New York, Gar Logan mentioned that no one had any real devotion to the team. Beast Boy and Flamebird attempted to recruit the DEO orphans as the new version of Titans West, but they declined. Eventually, the new West Coast group of Titans dissolved before it even truly began.
Teen Titans III
First Appearance: Teen Titans [third series] #1
Recently, A mysterious conglomerate known as Optitron offered to sponsor the Titans and Young Justice after summoning them to San Francisco. Before any decisions could be made, a mysterious cybernetic girl known as Indigo emerged from the future. Unwittingly, she somehow activated a rogue Superman android, resulting in the deaths of Troia and Omen. At Troia's funeral, Nightwing disbanded the Titans.
Meanwhile, members of Young Justice, especially Wonder Girl, felt responsible for the tragic deaths. This led Wonder Girl, Robin, Impulse and Superboy to form a new group of Teen Titans under the guidance of the more experienced Cyborg, Starfire and Beast Boy.
Located in San Francisco Bay beside the Golden Gate Bridge, the newest Titans Tower serves as a state-of-the-art training center as well as an uber-crash-pad; this Titans Tower is the weekend destination for the young heroes of today.