What is voice acting and why is it important to animation?

There was a time, in the days of silent films, when all you needed to finish off an animation was an audio track. Characters didn't talk; they bounced happily to the music, with the occasional sound effect orchestrated into the track. Nowadays, though, animated characters talk - they talk, they sing, and they make just about every interesting noise you can think of. But that speech doesn't happen by some strange magic of pencil and paper; animators can't generate voices out of thin air. The voices of your favorite characters are actually the voices of actors - some famous screen and stage actors, and some professional voice actors who devote their careers to lending sound and life to the animations that we love.