Bart Allen, 30th century grandson of Barry Allen (2nd Falsh now dead), inherited the powers of his bloodline but no control over his speed. Hypermetabolize, Bart aged fourteen years in the space of his first two years and would have died of old age had his grandmother Iris Allen not brought him to the 20th century, where Wally West, (current Flash), found a way to temper Bart's accelereted system. Since Bart grew up exclusively in a VR enviroment set to match his speed, he still thinks the world around him has a big "reset" button and doesn't really understand the concept of danger. Poster child for the judmentally impaired, Bart-a.k.a. Impulse, the most fitting super-hero name in history--moves straight from idea to deed without ever pausing along the way for the stage others call "thinking". He is kept alive solely through the effort of his mentor, Max Mercury. Posing as Max' nephew, Bart lives in a small, slow Southern town. He belives this is a punishment. He is correct.
Recently Bart acquire a new power, the ability to create duplicates of himself. This ability surfaced when he heroicaly stepped in front of the Hyperbeam, that future Carol built, to save the future Earth (See Dark Tomorrow storyline). The duplicates have the ability to move foward and backward in time.