Like the content of television, newspapers, magazines, books and radio, the messages on the Internet range from the profound to the outrageous. But the Net makes it cheaper and easier than most mainstream-dominated media to broadcast your message to a large potential audience. Anyone can create web pages. Most Internet service providers and online services offer customers server space to publish their efforts on the Net. Whether anyone will look at them is another question. The radical difference between the Internet and other mass media is that while anyone can make a bid for attention at http something or other, there is no central audience regularly tuning to channel 2 or 4 or 7 -- no easy way to command major market share. If websites were channels, there would be tens of millions of them on the Net, which helps explain why every muffler shop, pizzeria and hardware store seems to have one, as well as every crank. And that is precisely what gives parents pause when they wonder what strange ideas and people their children may encounter on the electronic frontier.