This 2009 ZDNet piece captures a moment of rare candor from Sir Tim Berners-Lee, the inventor of the World Wide Web, admitting that the // in every URL you've ever typed was, in his own words, "a bit of a mistake." It's the kind of small historical artifact that technical audiences tend to love — a design decision made in a hurry decades ago that now sits, immutable, in trillions of hyperlinks.

The double slash originates from Unix filesystem conventions Berners-Lee borrowed when sketching out the URL syntax at CERN in 1989. The :// separator distinguishes the scheme (http, ftp, file) from the host, but the two slashes specifically signal an authority component — a hostname follows. In hindsight, Berners-Lee has noted that a single character would have worked just as well, and would have saved:

• Untold billions of keystrokes over the web's lifetime
• Kilobytes shaved off every printed document, business card, and billboard containing a URL
• Simpler parsing logic in every browser, curl invocation, and URL library ever written

Why does this deserve a second look in 2026? Because it's a perfect illustration of protocol path dependency — the phenomenon where a trivial early choice becomes impossible to undo once the ecosystem grows around it. We're living through the same dynamic right now with things like the JSON spec's lack of comments, HTTP/1.1 header case-insensitivity quirks, and the way we're bolting agent-to-agent protocols onto tools originally designed for humans clicking buttons.

Engineers building new protocols today — MCP, agent handoff schemes, whatever comes next for the "AI web" — would do well to sit with this story for a minute. The // wasn't malicious or lazy; it was a reasonable choice by a smart person under time pressure. And now it's forever. Every design decision you make with the assumption that "we can fix it later" deserves the Berners-Lee test: if this survives thirty years unchanged, will I be embarrassed?

The article itself is short — a quick read from the pre-social-media web that's aged into something almost quaint. But it's a useful reminder that even the people who invent the foundations of the modern world get to look back and cringe.