Alias: Barry Allen?
First Appearance: Showcase #4 (1956)
Powers: Fastest dude ever, heals quickly, can vibrate himself through matter, can vibrate into different realities, with the assistance of the Cosmic Treadmill he can travel through time, is able to lend his powers to others
Other Media: Appeared on many cartoons, had his own live-action TV series in the 90’s, appeared on Legend of the Superheroes (a failed Justice League spinoff of the 60’s Batman show) and the live-action Justice League of America TV movie, was kind of a big deal in Daddy Day Care
Warning: the history of the Flashes involves some time travel fuckery and in a lot of these cases, I’m just as confused as you are.
The Golden Age Flash was Jay Garrick. Maybe five people care about him and they’re all mad I just said this. Moving on.
Barry Allen (you know, from Catch Me If You Can) became the Flash in the 50’s. He was a forensic scientist who got splashed with chemicals while being shocked by lightning. That gave him the powers to run super fast and he decided to be altruistic with it, naming himself the Flash after his favorite comic book hero. He garnered one of the best rogues galleries in comics, got himself a sidekick in Kid Flash (his nephew Wally West, who got his powers in a similar way) and a fiancé in Iris West.
One of his villains was Professor Zoom, who looked identical to Flash except for having a reverse color scheme. Zoom was from the future and had powers and an appearance that were just like Barry’s because he was a huge Flash fanboy who went insane. Jealous of Flash’s relationship with Iris, Zoom killed her by vibrating his hand through her head. Barry tried to move on and later got engaged to another woman, but when Zoom attempted to meddle in that, a threatened Flash ended up breaking his neck and killing him. Flash was put on trial for murder and it got really weird because it turns out Iris was really from the same future era as Zoom and she was alive there somehow, so he ran to the future and spent some time with her.
Flash returned to the present during the big Crisis on Infinite Earths event. It’s there that he faced down the villain Anti-Monitor and ran circles around his big world-destroying master weapon, destroying it via vortex. The stress on running faster than he had ever run and being unable to let up tore Flash apart and caused him to painfully decay as he powered on, screaming that he had to save the world one last time. He ruined Anti-Monitor’s plans, but at the cost of his own life. Kid Flash discovered the empty red tights – the only thing that remained of Barry – and swore that he would take up the mantle and make him proud.