Last week, Microsoft CEO Satya Nadella appeared at an industry conference and provided a series of insider insights into the future of the company, and where he sees the firm having the biggest successes. It was surprisingly non-evasive and deeply insightful.

Mr. Nadella's comments came during a lengthy Q & A session at the Code Conference last week Rancho Palos Verdes, California. He was interviewed by tech industry icon Walt Mossberg and his sidekick Kara Swisher.

And he covered a lot of topics, some of which I covered previously in Nadella: Microsoft Will Not Sell Xbox or Bing. Most notably, and as the name of that article suggests, Mr. Nadella tossed cold water on calls for the firm to sell or spin off Xbox and Bing. But I'm interested in what he said about Microsoft's new businesses, and about the future.

As you are likely aware, when then Apple CEO Steve Jobs introduced the first iPad four years ago, he said that the device was the start of the start of the so-called "post-PC" era, one in which users would increasingly drop PCs ("trucks" using an increasingly tired metaphor) for tablets and smartphones ("cars").

At the time, Microsoft bristled at this description, arguing that we were in fact entering a "PC plus" era, in which these new devices would be used alongside PCs. And PCs would of course evolve to take on the more positive traits of devices, like instant-on, better battery life, simplicity, and so on.

I still believe that Microsoft's term is the more correct one, and while anyone can look at the falling PC sales from the past few years and raise a contrary objection, the truth is that the market is simply settling out. The PC drop-off is ending, plateauing. And, surprise, tablets sales are falling off as well. Apple sold fewer iPads in the most recent quarter than it did in the year-ago quarter, for the first time ever.

But Microsoft isn't patting itself on the back for winning the naming wars. Instead, Mr. Nadella offered up yet another name for this new era: He confusingly called it the "post-post-PC" era.

What?

Reading between the lines—which in this case is required as Nadella never really expanded on this concept—I'd guess that what he's suggesting is that the neat delineations of the past—PCs, tablets, and smartphones are easily understood product categories—are increasingly being blurred. First, crossover devices like phablets (part phone, part tablet), mini-tablets, and hybrid PCs (part tablet, part PC) are not so easily categorized, and they often replace two previous device types. And wearable, embedded, and other non-traditional form factor PCs are exploding in use, leading to the terrible term "Internet of Things." It's messy.

Microsoft will of course continue to focus on these PCs, tablets and phones, of course, and on the gray-area crossovers. It will participate in the Internet of Things, and in wearable computing. It's looking forward.

But the notion of a "post-post-PC" world echoes a comment outgoing CEO Steve Ballmer made earlier this year, when he suggested that Microsoft may have simply missed the current generation of personal computing, meaning the post-PC/PC-plus era. Other companies—Apple and Google, and Samsung—have dominated this generation. So maybe it's time to look ahead to the next era.

That, in a way, is the real message behind "post-post-PC." That Microsoft no longer cares what the current or previous era was called. Again, it's looking forward.

So what does forward look like?

That's where it gets a bit nebulous. The problem with the future is that there's no real way to know what the Next Big Thing is. But Microsoft has a lot of resources around research and development that could help the firm not just find that thing—or those things—but push them into the market. (Only Google arguably has a similar level of investment in R&D.)

"Our own ability to have an idea and go after an idea and make that happen [is], at the end of the day, what defines success," he said. He's not looking to make an acquisition but rather is looking internally for that next big product.

"I think we have to build something big," he said. "If along the way we have to buy things, that's fine. But we have to build something big. We've built three big things, three and half if [we] add Xbox into it. It's time for us to build the next big thing."

This is interesting because we often focus on Microsoft's success at migrating its traditional, on-premises enterprise products into cloud-based subscription services, and over the past year, the firm has really settled into a nice groove. But at the end of the day, this stuff is really just the same stuff, thematically, as the Windows/Windows Server and Office successes (the three big things) on which Microsoft is built. The firm needs something new, something different if it is expected to keep growing. This means new software, new platforms.

The only peek we got at this future was a compelling demo of Skype Translate, a years-old research project that will finally see the light of day this year. Skype Translate translates the spoken word in real time, letting two people who don't speak each other's languages have a fairly normal conversation. The demo involved an English speaker and a German speaker and would have been at home in a science fiction movie.

Is this the future of Microsoft? It's one future, or at least part of the future. But as we move past traditional computing devices into a world in which everything is basically a connected computing device, this kind of seamless interconnectivity isn't just exciting and enabling, it's obvious and required.

I wonder what else Microsoft has up its virtual sleeve.