People have been predicting the “death of the PC” for years, to little effect. But in the PC world, market forces have never collided quite like they are now.

The rise of the living Web — a place populated with your personal content — has given birth to the “cloud.” The iPhone and natural human interfaces have dramatically changed the way we physically interact with our machines, peeling away layers of abstraction.

Those two forces are converging to make computing more human by removing the confusing language of machines.

We’re about to cross over a threshold where the devices we use really do become far less like a computer — both in how they function and where their bits are stored — and more personal, too. We’re watching the small drops of rain turn into a full downpour, and the flood is just around the corner.

At Apple’s Worldwide Developers Conference this year, Steve Jobs told an audience of eager programmers that his team had been working for 10 years to “get rid of the file system [on computers] so the user didn’t have to worry about it.” A month earlier, Google representatives took the stage at their annual developer conference and introduced a type of laptop that gets rid of not only the file system but nearly the entire computer, offering users nothing more than a Web browser with which to navigate their digital life.

Even Microsoft recently introduced its latest version of Windows (No. 8 for those keeping count) coupled with a simple, touch-friendly new way to navigate your computer, based on the company’s phone operating system.

Last month, Apple introduced the latest version of its operating system for Macs to the public: OS X Lion. The software is notable not just for what it adds to the user experience but also what it hides or removes completely.

Borrowing heavily from the logic of the iPad and iPhone, Lion allows and encourages applications to run in a “full screen” mode that removes familiar pieces of the operating system such as the menu bar. It also demands that the user focus on one application at a time. You’re either in it, or you’re not.

Why is this significant? Largely because interface designers have spent the past quarter-century trying to figure out how to better manage windows — literally, how to un-clutter the windows in which your information is kept. As anyone who has ever struggled to carry on an instant message session while browsing the Web, checking e-mail and keeping an eye on Twitter can tell you, that isn’t so easy.

However, with the advent of full-screen, touch-focused devices such as the iPad, user behavior is starting to change, and that’s changing the way our computers will behave, too. Full-screen applications might not necessarily make your life easier, but they’ll definitely alter how you interact with your PC.

Elsewhere in Lion, multi-finger gestures replicate the kinds of swipes and flicks we’re becoming accustomed to on the screens of mobile devices, an obvious foreshadowing of a generation of PCs that do away with the keyboard and track pad altogether. A simplified, iPad-like grid of icons called Launchpad can be used to open applications. Even scroll bars have vanished. In fact, the company is doing nearly everything it can to obscure the “computer” in Lion.

And Apple has gotten rid of that file system; your documents are saved in invisible “versions” that can be recalled from any point in your editing process. At another conference last year, Jobs said PCs are more like trucks — heavy-duty devices that most people don’t really need — and would be relegated to big, messy jobs that a smaller car (say, an iPad) couldn’t handle. It now seems that those “trucks” might be due for an overhaul. Microsoft agrees, having tuned the forthcoming version of Windows to utilize “tiles” that are straight out of a touch-screen environment.

But it’s not just behavior on the screen that’s being altered, it’s also the behavior behind and beyond what you can see. Google, a company known best for search and its mobile operating system, Android, has just introduced an operating system dubbed Chrome OS. If the name sounds familiar, it should: The system is built upon the company’s popular Chrome Web browser.

In fact, the devices being sold that run Chrome OS (Chromebooks) are nothing more than notebooks running that browser. But Chrome OS goes much deeper than just an interface; the system demands that nearly all of your data — documents, e-mail, music and more — are stored not on the laptop itself but in the cloud. A Chromebook has nearly no physical storage and no way to add physical storage.

Apple wants a piece of that action, too. The company’s iCloud service will do largely what Google and others are already doing: moving your content away from the device on your desk, or in your hand, and into a distant data center that’s always on, always accessible from any device, and most importantly, nearly impervious to damage — physical or otherwise.

Something very big is happening in computing right now. We’re moving away from closed, disconnected, windowed environments toward something dramatically different. This isn’t like going from a command line in DOS to the graphical environment of Windows. It’s more like going from driving a car to a shuttle launch.

What will happen over the next few years in user interface design and decentralized cloud systems will make the previous 20 years seem tame by comparison. We’ve crossed over from a long, slow evolution to an explosive revolution in what a computer is and how you use it — and there’s no looking back.

Joshua Topolsky is the founding editor-in-chief of the Verge, a technology news Web site debuting this fall, and the former editor-in-chief of Engadget. He is the resident tech expert for NBC’s “Late Night With Jimmy Fallon” and has appeared on CNN, Fox News, Bloomberg TV and G4’s “Attack of the Show.”