Is Pinterest a social network?

Silbermann paused, glanced up at the hot stage lights, and responded.

Pinterest is a “catalog of ideas,” he told attendees at this year’s Fortune Brainstorm Tech conference. “I think that’s a very different thing than a social network.” The objectives of the two are different, he said. On a social network, you upload photos for other people to like. Pinterest, on the other hand, is self-serving.

“Our hope is that when we show you the right idea you go out and do that thing,” he said. He likened Pinterest to “a catalog that’s hand-picked” for his users.

Which explains the company’s recent foray into “Buy” buttons. The highly-funded startup—$11 billion at last count, putting it in the top 10 on Fortune‘s Unicorn List—is in search of revenue worth crowing about. The best way to do it is to encourage the more commercial aspects of that catalog concept.

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“We have a really clear understanding when people begin to plan events,” Silbermann said. (He added that while the majority of his users remain women, men are its fastest-growing segment. As is international: 40% of Pinterest users live outside the U.S. and the number is growing.)

But transactions are still a work in progress for the company, Silbermann allowed. “It’s a pretty hard problem,” he said. Buying a product or service through Pinterest should feel seamless—“easy and light and fun.” But working with “thousands” of merchants is no small undertaking. “It took time to do it right,” he said. Pinterest began working on the effort last summer.

Today, Pinterest takes no cut of transactions it processes, Silbermann said. It’s in growth mode. “We want to create a platform for product and service providers to [reach] customers,” he said. “People go to Pinterest because they’re looking for inspiration from their life.”

And as for Promoted Pins, the company’s other revenue-generating effort? It’s coming along, Silbermann said.

“Advertising has a bad word associated with it,” he said. “A lot of ads really suck. They’re really ugly. They detract from the experience. You want Promoted Pins to feel like the ideas you want to make your own.”

On the business side, “advertisers have a lot of platforms to think about,” he added. Pinterest wants to help them understand Pinterest better so that they create something better for users.

With all of these revenue-generating efforts afoot, is Pinterest—more than 500 employees strong and still growing—thinking about an IPO? No, Silbermann said. “We don’t have any short-term plans to go public.” Public companies have predictable revenue, he said. The inference: Pinterest does not.

For now, priorities are international expansion—western Europe, Japan, and Brazil, he said—improving discovery and building out the money machine.

But the easiest decision for Pinterest is already made: making it image-focused. Said Silbermann: “No amount of technology is going to change the fact that people process information visually.”

For more coverage of this year’s Fortune Brainstorm Tech, click here.