In early 2004, some of the frost left behind by the dot-com bust had begun to melt away. And though funding for tech start-ups was nowhere near the stratospheric levels of 2018, the year would come to be known as one that defined the modern social Web. That February, Mark Zuckerberg launched TheFacebook.com out of his Harvard dorm room. Ev Williams left Google to found Odeo, the precursor to Twitter. And Paul Graham, an entrepreneur in Cambridge, devised a way to fix the Internet.

Graham and his then-girlfriend, Jessica Livingston, a marketing executive, contributed $100,000 to what Graham had dubbed his “little experiment”—a way to give scrappy teams of programmers a leg up, outside the venture-capital churn of Silicon Valley. He refused to call it a tech incubator, but did give it a name: Y Combinator. It would be a summer experiment, granting just $6,000 per applicant (enough, he figured, for them to eat and pay for a sublet; not enough to bog them down). He posted a link to the application on his popular blog, and in just 10 days had received more than 200 ideas, many of them viable. Clearly, the idea had struck a chord. Graham told Livingston, “You better quit your job.” She invited the most formidable applicants to Cambridge for interviews.

The pair, along with two other partners, met with 19-year-old Sam Altman, who pitched Loopt, a location-aware social-networking application (yes, he’d have a spot in Y Combinator). Yale students Justin Kan and Emmett Shear pitched a calendar application (yes). Stanford freshman Aaron Swartz—a minor legend in certain Internet circles, having co-written the RSS 1.0 standard, a new way of syndicating Web content, at 14, and later a code layer for the online-copyright sharing system Creative Commons—was accepted into the program. Then there was a pair of seniors from the University of Virginia, Alexis Ohanian, and Steve Huffman, who proposed a phone-based food-ordering system for which they had no technological backbone, and which they’d dubbed My Mobile Menu, or MMM, to mimic a satisfied murmur.

The concept, to Graham, was full of holes. For one, it was too early to be focused on mobile development—few people browsed the Internet on their cell phones, and text messaging and BlackBerry Messenger were still in their infancy. Instead, Graham had an entirely different sort of Internet business in mind. To explain it, he’d phoned Huffman and Ohanian halfway through their 18-hour train trip back to Charlottesville. Though he found their concept unappetizing, he liked the pair of fresh-faced students—particularly Huffman, the hacker with a shock of gold hair and oversized wire-rim glasses whom Livingston had dubbed “muffin.” He asked them to turn around.

Book Cover: From Hachette Books.

The pair conferred, and within minutes, they’d decided: What the hell. The train pulled to a stop, and Huffman and Ohanian rushed to the door. With their bags, they hopped down and ran across the active tracks. When the next train heading north to Boston pulled in, they tried to explain the situation to the conductor, who, exasperated by their manic enthusiasm, reluctantly let them on.

Once they’d returned to Graham’s office at 135 Garden Street, Graham wasted no time. You know who was on to something, Graham mused: Slashdot. He pulled up the site and showed the young men its trove of interesting but somewhat mainstream tech-centric links. There was also, similarly, Delicious (known often by its curious domain name, del.icio.us), a site people used to bookmark their favorite Web sites and articles, or to find topical content based on freeform hashtags suggested by users. Co-created by former Morgan Stanley analyst Joshua Schachter, Delicious had earned Graham’s esteem after it directed significant traffic to some of his essays, which had been boosted to its “popular” page. Clicking on that particular tab yielded a delightful mix of content, from highly technical Linux how-tos to general-interest links to Saturday Night Live clips and Roger Ebert’s best-movie list for the year.