The Silver and Bronze Ages
Robin, Aqualad, and Kid Flash teamed up for the first time in 1964's THE BRAVE AND THE BOLD #54, in which they confronted the evil Mister Twister. They adopted the name “Teen Titans” in that same year's THE BRAVE AND THE BOLD #60, which saw them fight alongside Wonder Girl for the first time. The team earned their first self-titled comic with 1966's TEEN TITANS #1. Throughout the Silver and Bronze Ages they admitted many other young heroes into their ranks, including Speedy, Aquagirl, Lilith, Bumblebee, Mal, and Duella Dent (a.k.a. The Joker's Daughter).
The Coming of Trigon (THE NEW TEEN TITANS #1-6 1980)
The origin story of the “New Teen Titans” came years after the original Teen Titans has formed. When the half-demonic empath Raven needed help to prevent her father, the demon lord Trigon, from conquering the mortal plane, she manipulated Robin, Starfire, Cyborg, Wonder Girl, Beast Boy (then known as Changeling), and Kid Flash into re-forming the Teen Titans to aid her.
During this arc, the team also came face to face with Deathstroke the Terminator (a.k.a. Slade Wilson) for the first time. He would go on to become one of their greatest enemies.
"The Judas Contract" (TALES OF THE TEEN TITANS #42-44, Annual #3, 1984)
Fostering a grudge after the death of his son, Grant, which he believed to be the Titans' fault, Slade Wilson launched a scheme to infiltrate and dismantle the team from the inside. He hired Terra, a young metahuman with the ability to physically manipulate earth, to become a mole within their ranks, earning the trust and friendship of the team – especially Changeling, who developed a bit of a crush on her.
Betraying their trust forced cracks in the very bedrock of the team. It was only with the help of Slade's son, Joey Wilson, and his estranged wife, Adeline, that the Titans were able to prevent Slade from destroying them completely. Joey later adopted the code name Jericho and joined the Titans permanently.
"Who Is Donna Troy?" (NEW TITANS #50-54, 1988)
A deep dive into the complicated history of one of the original Teen Titans, “Who Is Donna Troy?” was an operatic look at the origin and continuity of Wonder Girl. Sparked by a visit from a time-displaced Phoebe – a harbinger of the "Titans of Myth" -- Donna was forced to reconcile the fact that everything she believed about herself (that she was an orphan girl rescued from disaster by Wonder Woman) was a lie. Instead, she had been saved by cosmic beings and raised as part of their society. The story arc resulted in Donna changing her super hero code name to Troia.
JLA/TITANS: THE TECHNIS IMPERATIVE (1998)
Following the disbandment of the Titans, the technological half of Cyborg's body and brain were infected by an evil entity known as Technis. Losing control of both his body and mind, he transformed into a giant, inorganic planet, and sent probes to kidnap all former Titans, bringing them into specially constructed artificial dream states.
The Justice League viewed the Technis planet as a threat, but the Titans, once freed from their cells, argued that Victor Stone was still alive inside the technological monstrosity, and that the kidnapping of his former teammates was a cry for help. The resulting fight for Cyborg's soul pitted the extended roster of the Justice League against every Super Hero who’d ever called themself a Titan.
After Cyborg was eventually saved, the Titans decided to reform, establishing a new roster under the leadership of the original team: comprised of Nightwing, Donna Troy, Starfire, Beast Boy, Cyborg, Wally West, and Arsenal.
TITANS/YOUNG JUSTICE: GRADUATION DAY (2003)
When a time-traveling incarnation of Brainiac, Brainiac 8, arrived in the present, badly damaged, it frantically searched out cybernetic components to repair itself. This led it to attack both Young Justice and the Titans, in an effort to get to Cyborg. They managed to fight it off, but the battle left each team in disarray.
Brainiac 8's hunt for cybernetic parts led it to reactivate a defunct Superman Android, which attacked and killed both Lilith Clay and Donna Troy before the remaining Titans and members of Young Justice were able to bring it – and Brainiac 8 itself – down for good. The critical losses forced Nightwing to take a hard look at each team. Heartbroken and in mourning, he disbanded both of them.
"A Kid's Game" (TEEN TITANS #1-7, 2003-2004)
Following the disbanding of both Young Justice and the Titans, Starfire, Cyborg and Beast Boy decided to take matters into their own hands by reaching out to the former core members of Young Justice and offering them a position on a newly formed Teen Titans team.
Tim Drake, Cassie Sandsmark, Connor Kent, and Bart Allen made up the initial roster of the new team, though it rapidly expanded to include an all-new generation of young heroes looking for a place to call their own.
TEEN TITANS: YEAR ONE (2008)
2008’s Year One served as a modern retelling of the earliest Teen Titans adventures, and featured a young Dick Grayson, Donna Troy, Roy Harper, and Wally West forming the team officially for the first time. After a cosmic monster named Antithesis psychically manipulated their respective mentors, the Titans were forced to act, beating their elders in a fight that wound up proving their viability as an independent DC Super Hero team.
The New 52 (2011)
Following the events of 2011’s FLASHPOINT, the history of the Teen Titans was dramatically altered. In this new continuity, Wally West had been removed from the timestream and Dick Grayson had never founded the team. At least, that's what the world believed to be true.
A cosmic anomaly caused memories to reawaken in various former Titans, like Nightwing, Arsenal, Lilith Clay, Aqualad and Gnarrk; forcing them to confront the fact that they had all been teammates once before. But that someone – or something – had tampered with their memories. They were able to track down the source of the anomaly, the demonic Mister Twister, who’d first brought the original Teen Titans together. Because of Mister Twister's otherworldly abilities, the Titans had been psychically wiped of all memories of the event. But as their memories resurfaced, so did Twister's powers.
With their knowledge of their own history restored, the Titans officially reformed, and confronted Twister yet again. This time defeating him, hopefully, once and for all.
"The Lazarus Contract" (2017)
Following the officially post-Rebirth reformation of both the Teen Titans and the adult Titans, ghosts from both teams’ past were in no short supply. Slade Wilson, still harboring grief over the loss of his eldest son, Grant, hatched a plan that involved siphoning the Speed Force out of Kid Flash and The Flash, to enable him to travel through time to the night Grant had been killed and save his life, while deleting the Titans from the present.
The Teen Titans and Titans were then forced to save Slade's life before his plan could consume him, despite considering that a world without Deathstroke might be a better place.