Today, 30 years on from my original proposal for an information management system, half the world is online. It's a moment to celebrate how far we've come, but also an opportunity to reflect on how far we have yet to go.

The web has become a public square, a library, a doctor's office, a shop, a school, a design studio, an office, a cinema, a bank, and so much more. Of course with every new feature, every new website, the divide between those who are online and those who are not increases, making it all the more imperative to make the web available for everyone.

And while the web has created opportunity, given marginalised groups a voice, and made our daily lives easier, it has also created opportunity for scammers, given a voice to those who spread hatred, and made all kinds of crime easier to commit.

Against the backdrop of news stories about how the web is misused, it's understandable that many people feel afraid and unsure if the web is really a force for good. But given how much the web has changed in the past 30 years, it would be defeatist and unimaginative to assume that the web as we know it can't be changed for the better in the next 30. If we give up on building a better web now, then the web will not have failed us. We will have failed the web.

To tackle any problem, we must clearly outline and understand it. I broadly see three sources of dysfunction affecting today's web:
 1. Deliberate, malicious intent, such as state‑sponsored hacking and attacks, criminal behaviour, and online harassment.
 2. System design that creates perverse incentives where user value is sacrificed, such as ad‑based revenue models that commercially reward clickbait and the viral spread of misinformation.
 3. Unintended negative consequences of benevolent design, such as the outraged and polarised tone and quality of online discourse.

While the first category is impossible to eradicate completely, we can create both laws and code to minimize this behaviour, just as we have always done offline. The second category requires us to redesign systems in a way that change incentives. And the final category calls for research to understand existing systems and model possible new ones or tweak those we already have.

You can't just blame one government, one social network or the human spirit. Simplistic narratives risk exhausting our energy as we chase the symptoms of these problems instead of focusing on their root causes. To get this right, we will need to come together as a global web community.

At pivotal moments, generations before us have stepped up to work together for a better future. With the Universal Declaration of Human Rights, diverse groups of people have been able to agree on essential principles. With the Law of Sea and the Outer Space Treaty, we have preserved new frontiers for the common good. Now too, as the web reshapes our world, we have a responsibility to make sure it is recognised as a human right and built for the public good. This is why the Web Foundation is working with governments, companies and citizens to build a new Contract for the Web.