The Web is critical not merely to the digital revolution but to our continued prosperity—and even our liberty. Like democracy itself, it needs defending.

The world wide web went live, on my physical desktop in Geneva, Switzerland, in December 1990. It consisted of one Web site and one browser, which happened to be on the same computer.

The simple setup demonstrated a profound concept: that any person could share information with anyone else, anywhere. In this spirit, the Web spread quickly from the grassroots up. Today, at its 20th anniversary, the Web is thoroughly integrated into our daily lives. We take it for granted, expecting it to “be there” at any instant, like electricity.

The Web as we know it, however, is being threatened in different ways. Some of its most successful inhabitants have begun to chip away at its principles. Large social-networking sites are walling off information posted by their users from the rest of the Web. Wireless Internet providers are being tempted to slow traffic to sites with which they have not made deals. Governments—totalitarian and democratic alike—are monitoring people’s online habits, endangering important human rights.

If we, the Web’s users, allow these and other trends to proceed unchecked, the Web could be broken into fragmented islands. We could lose the freedom to connect with whichever Web sites we want.

Why should you care? Because the Web is yours. It is a public resource on which you, your business, your community and your government depend. The Web is also vital to democracy, a communications channel that makes possible a continuous worldwide conversation. The Web is now more critical to free speech than any other medium.

Yet people seem to think the Web is some sort of piece of nature, and if it starts to wither, well, that’s just one of those unfortunate things we can’t help. Not so. We create the Web, by designing computer protocols and software; this process is completely under our control. We choose what properties we want it to have and not have. It is by no means finished (and it’s certainly not dead).

If we want to track what government is doing, see what companies are doing, understand the true state of the planet, find a cure for Alzheimer’s disease, not to mention easily share our photos with our friends, we the public, the scientific community and the press must make sure the Web’s principles remain intact—not just to preserve what we have gained but to benefit from the great advances that are still to come.

Open, royalty-free standards that are easy to use create the diverse richness of Web sites, from the big names such as Amazon, Craigslist and Wikipedia to obscure blogs written by adult hobbyists and to homegrown videos posted by teenagers.

Openness also means you can build your own Web site or company without anyone’s approval. When the Web began, I did not have to obtain permission or pay royalties to use the Internet’s own open standards, such as the well-known transmission control protocol (TCP) and Internet protocol (IP).

Similarly, the Web Consortium’s royalty-free patent policy says that the companies, universities and individuals who contribute to the development of a standard must agree they will not charge royalties to anyone who may use the standard.

In contrast, not using open standards creates closed worlds. Apple’s iTunes system, for example, identifies songs and videos using URIs that are open. But instead of “http:” the addresses begin with “itunes:,” which is proprietary. You can access an “itunes:” link only using Apple’s proprietary iTunes program. You can’t make a link to any information in the iTunes world—a song or information about a band. You can’t send that link to someone else to see. You are no longer on the Web. The iTunes world is centralized and walled off. You are trapped in a single store, rather than being on the open marketplace. For all the store’s wonderful features, its evolution is limited to what one company thinks up.

Keeping the web universal and keeping its standards open help people invent new services. But a third principle—the separation of layers—partitions the design of the Web from that of the Internet.

This separation is fundamental. The Web is an application that runs on the Internet, which is an electronic network that transmits packets of information among millions of computers according to a few open protocols. An analogy is that the Web is like a household appliance that runs on the electricity network.

Although internet and web designs are separate, a Web user is also an Internet user and therefore relies on an Internet that is free from interference. In the early Web days it was too technically difficult for a company or country to manipulate the Internet to interfere with an individual Web user. Technology for interference has become more powerful, however.

Net neutrality maintains that if I have paid for an Internet connection at a certain quality, say, 300 Mbps, and you have paid for that quality, then our communications should take place at that quality. Protecting this concept would prevent a big ISP from sending you video from a media company it may own at 300 Mbps but sending video from a competing media company at a slower rate. That amounts to commercial discrimination. What if the ISP made it difficult for you to go to Web sites about certain political parties, or religions, or sites about evolution?

Unfortunately, in August, Google and Verizon for some reason suggested that net neutrality should not apply to mobile phone–based connections. Many people in rural areas from Utah to Uganda have access to the Internet only via mobile phones; exempting wireless from net neutrality would leave these users open to discrimination of service.

Other threats to the web result from meddling with the Internet, including snooping. In 2008 one company, Phorm, devised a way for an ISP to peek inside the packets of information it was sending. The ISP could determine every URI that any customer was browsing. The ISP could then create a profile of the sites the user went to in order to produce targeted advertising.

Accessing the information within an Internet packet is equivalent to wiretapping a phone or opening postal mail. The URIs that people use reveal a good deal about them. A company that bought URI profiles of job applicants could use them to discriminate in hiring people with certain political views, for example. Life insurance companies could discriminate against people who have looked up cardiac symptoms on the Web. Predators could use the profiles to stalk individuals. We would all use the Web very differently if we knew that our clicks can be monitored and the data shared with third parties.

Free speech should be protected, too. Earlier this year Google accused the Chinese government of hacking into its databases to retrieve the e-mails of dissidents. The alleged break-ins occurred after Google resisted the government’s demand that the company censor certain documents on its Chinese-language search engine.

Totalitarian governments aren’t the only ones violating the network rights of their citizens. In France a law created in 2009, named Hadopi, allowed a new agency by the same name to disconnect a household from the Internet for a year if someone in the household was alleged by a media company to have ripped off music or video.

After much opposition, in October the Constitutional Council of France required a judge to review a case before access was revoked, but if approved, the household could be disconnected without due process.

In the U.K., the Digital Economy Act, hastily passed in April, allows the government to order an ISP to terminate the Internet connection of anyone who appears on a list of individuals suspected of copyright infringement.

In September the U.S. Senate introduced the Combating Online Infringement and Counterfeits Act, which would allow the government to create a blacklist of Web sites—hosted on or off U.S. soil—that are accused of infringement and to pressure or require all ISPs to block access to those sites.

In these cases, no due process of law protects people before they are disconnected or their sites are blocked. Given the many ways the Web is crucial to our lives and our work, disconnection is a form of deprivation of liberty.

Looking back to the Magna Carta, we should perhaps now affirm: “No person or organization shall be deprived of the ability to connect to others without due process of law and the presumption of innocence.”

When your network rights are violated, public outcry is crucial. Citizens worldwide objected to China’s demands on Google, so much so that Secretary of State Hillary Clinton said the U.S. government supported Google’s defiance and that Internet freedom—and with it, Web freedom—should become a formal plank in American foreign policy. In October, Finland made broadband access, at 1 Mbps, a legal right for all its citizens.

Now is an exciting time. Web developers, companies, governments and citizens should work together openly and cooperatively, as we have done thus far, to preserve the Web’s fundamental principles, as well as those of the Internet, ensuring that the technological protocols and social conventions we set up respect basic human values. The goal of the Web is to serve humanity. We build it now so that those who come to it later will be able to create things that we cannot ourselves imagine.