SINCE I started writing this column in 1999, I've seen a thousand Internet businesses rise and die. I've watched the web go from a medium you access via dial-up to the medium you carry around with you on your mobile. Still, there are three myths about the Internet that refuse to kick the bucket. Let's hope the microgeneration that comes after the Web 2.0 weenies at last puts these misleading ideas to rest.

Myth: The Internet is free. This is my favorite Internet myth because it has literally never been true. In the very early days of the net, the only people who went online were university students or military researchers—the former got accounts via the price of tuition; the latter got it as part of their jobs. Once the Internet was opened up to the public, people could only access it by paying fees to their Internet service providers (ISPs). And let's not even get into the fact that you have to buy a computer or pay for time on one.

I think this myth got started because pundits wanted to compare the price of publishing or mailing something on the Internet to the price of doing so using paper or the postal service. Putting up a website on the web is "free" only if you pretend that you don't have to pay your ISP and a web-hosting service to do it. No doubt that's cheaper than printing and distributing a magazine to thousands of people. But it's not free.

Same goes for email. Sure it's "free" to send an email, but again you're still paying your ISP for Internet access to send that letter. The poisonous part of this myth is that it sets up the false idea that the Internet removes all barriers to free expression. The Internet removes some barriers but erects others. You can get few free minutes online in your local public library, maybe, and set up a website using a free service (if the library's filtering software allows that). But will you be able to catch anyone's attention if you publish under those constraints?

Myth: The Internet knows no boundaries. Despite the Great Firewall of China, an elaborate system of Internet filters that prevent Chinese citizens from accessing websites not approved by the government, many people still believe that the Internet is a glorious international space that can bring the whole world together. When the government of a country like Pakistan can choose to block YouTube—which it has and does—it's impossible to say the Internet has no boundaries. The Internet does have boundaries, and they are often drawn along national lines.

Of course, closed cultures are not the only source of these boundaries. Many people living in African and South American nations have little access to the Internet, mostly due to poverty. As long as we continue to behave as if the Internet is completely international, we forget that putting something online does not make it available to the whole world. And we also forget that communications technology alone cannot undo centuries of mistrust between various regions of the world.

Myth: The Internet is full of danger. Perhaps because the previous two myths are so powerful, many people have come to believe that the Internet is a dangerous place—sort of like the "bad" part of a city, where you're likely to get mugged or hassled late at night.

The so-called dangers of the Internet were highlighted in two recent media frenzies: the MySpace child predator bust, in which Wired reporter Kevin Poulsen discovered that a registered sex offender was actively friending and trolling MySpace for kids; and the harassment of web pundit Kathy Sierra by a group of people who posted cruelly Photoshopped pictures of her, called for her death and then posted her home address.

Despite the genuine scariness represented by both these incidents, I would submit they are no less scary than what one could encounter "in real life," offline. In general, the Internet is a far safer place for kids and vulnerable people than almost anywhere else. As long as you don't hand out your address to strangers, you've got a cushion of anonymity and protection online that you'll never have in the real world. It's no surprise that our myths of the Internet overestimate both its ability to bring the world together and to destroy us.

Annalee Newitz is a surly media nerd who is biased in favor of facts.

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