One of the most important functions of the BBC is to invest in original content, everything from Radio 3 to Strictly Come Dancing. But as the digital world challenges the television model and the way programmes are funded, the BBC's investment in programmes becomes even more important and that's particularly true of the money it puts into drama and children's programmes. But the most important function of the BBC is to be a trusted and reliable source of news and information and that's more important today than it ever was in the past, because the Internet is the home of rumour, gossip and paranoia. There can be no more acute expression of democracy than that there is a publicly funded news organisation that can criticise the government.