Andreessen writes that the reason he’s most excited about Rap Genius is because it’s creating a feature that was supposed be in Web browsers from the very beginning: annotations. But Andreessen dropped it at the very last minute.
Only a handful of people know that the big missing feature from the Web browser—the feature that was supposed to be in from the start but didn’t make it—is the ability to annotate any page on the Internet with commentary and additional information.
Back in 1993, when Eric Bina and I were first building Mosaic, it seemed obvious to us that users would want to annotate all text on the web—our idea was that each Web page would be a launchpad for insight and debate about its own contents. So we built a feature called “group annotations” right into the browser—and it worked great—all users could comment on any page and discussions quickly ensued. Unfortunately, our implementation at that time required a server to host all the annotations, and we didn’t have the time to properly build that server, which would obviously have had to scale to enormous size. And so we dropped the entire feature.
I often wonder how the Internet would have turned out differently if users had been able to annotate everything—to add new layers of knowledge to all knowledge, on and on, ad infinitum. And so, 20 years later, Rap Genius finally gives us the opportunity to find out.
Disclosure: Andreessen is a Business Insider investor.