I'm hearing in the news about this scandal involving signals being routed from catcher to the opponent's dugout and back to the batter. If you're not familiar with it, grab a paper. Here is my naive question about baseball in-general: Why is it the catcher that is telling the pitcher what ball to throw? What does the catcher know about the batter that the pitcher doesn't? And why hasn't this practice evolved so the pitcher is in-the-know about the batters?