Closed captioned for the hearing impaired.

Question. When the closed caption thing is happening, how is that happening? I mean, is someone watching the show I am, perhaps a few seconds ahead of me, and typing it in? Or do they have a script? If that is true, how do they do it for live events? The reason this came up, was because I had my TV on mute and the words were showing up from the closed caption. The funny thing was, it wasn't just the words, it had the person who said them listed. Not that that is huge, but it was a soap opera, so does that mean that the person doing the closed caption thing, has to watch the show and know the characters? If this was for Survivor or Amazing race, I'm in, but if I had to do it for a soap? I think I'd rather be unemployed. Perhaps I should look into this and, oh wait, nope, I just turned the mute off, curiosity gone.