The following script is from "TED Talks" which aired on April 19, 2015. Charlie Rose is the correspondent. Henry Schuster, producer. It has become a place where big ideas find a global audience. It is known simply as TED. And TED Talks are little presentations that anyone can watch online for free. There are TED Talks on almost every subject you can imagine: building your own nuclear reactor; stopping cyberbullies; exploring Antarctica; a better way to tie your shoes. But what sets TED Talks apart is that the big ideas are wrapped up in personal stories and they're mostly from people you have never heard of before. And it is those stories that have captured the imaginations of tens of millions of viewers around the world.