Just when you thought that things couldn't get any worse for the desktop, it gets kicked by a cold boot.

Industry tracker IDC is reporting that just 76.3 million PCs were shipped during this year's first quarter, down 13.9% from a year earlier.

Remember when Microsoft's (MSFT -1.84%) Windows 8 was supposed to make desktops and laptops popular again? It's amusing in retrospect. The percentage decline is the largest drop that IDC has reported since it began tracking quarterly shipment trends nearly two decades ago.

A meteor made dinosaurs extinct. A cloud is making PCs extinct.

Think about it. Everyone knows that smartphones and tablets are eating into the traditional PC market, but have you ever wondered why that's even possible? Have you wondered why Microsoft's mobile operating system hasn't been as dominant as what Apple (AAPL -0.57%) and Google (GOOGL 0.35%) have been cooking?

It's really all about the cloud.

We're spending more time on the Internet, and websites are largely operating system agnostic. Folks don't need a costly Windows license when an open source fix will do. Folks don't need a heavy-duty microprocessor, when the website will do all of the heavy lifting. Google's Android and Apple's iOS account for roughly 85% of the smartphone and tablet market, and that's good enough for most of the tasks performed by casual computer users.

The only real surprise in the data is that shipments to the U.S. -- off by 12.7% -- actually held up better than the world, on average. It won't be long before the desktop is merely a niche product for consumers.

It was nice knowing you, PC.