For many, the Internet of Things (IoT) remains a mystery -- words they've heard, maybe even a concept they understand, but not a relevant part of their life.

Of course, it wasn't that long ago when you could say the same thing about the Internet itself. Somewhere in the mid-1990s we moved from a time where, for the relatively small amount of people going online, the Internet meant the self-contained world of AOL, and into a time where nearly everyone was on the Web, which opened up into the wide expanse it has become.

For the IoT, the day when it moves beyond cool tech adopted by first movers has not yet come, but there are reasons to believe it's going to be as transformative as the Internet when it eventually happens. Here's a look at some facts about the IoT -- the world of smart devices connected to the Internet -- that may surprise you.

1. The IoT is going to be really big: From a modest $655.8 billion in 2014, International Data Corporation (IDC) expects IoT spending to grow to $1.7 trillion in 2020, with a compound annual growth rate of 16.9%.

"While wearable devices are the consumer face of the Internet of Things, and where recognition of IoT appears to begin, the real opportunity remains in the enterprise and public sector markets," said Vernon Turner, IDC's senior vice president and research fellow. "The ripple effect of IoT is driving traditional business models from IT-enabled business processes to IT-enabled services and finally to IT-enabled products, which is beginning to disrupt the IT status quo."

2. Microsoft (NASDAQ:MSFT) has a version of Windows just for IoT: Called Windows 10 IoT Core, the operating system is optimized for smaller devices, some of which don't have a display. The company has also enabled the OS to run with low-powered computers, including the Raspberry Pi 2 and 3, Arrow DragonBoard 410c, and MinnowBoard MAX. In theory, that offers a Windows-compatible solution that could make something as basic as your toaster or as powerful as high-end medical equipment Internet connectable and addressable.

Windows 10 IoT Core powers this clock radio. Source: Microsoft.

 3. The potential market is huge: As of 2016, less than 1% of all devices that could be connected to the Internet actually are, according to Cisco Systems (NASDAQ:CSCO). "That means that 10 billion out of the 1.5 trillion things that exist around the world are currently connected," wrote

4. The IoT can save us money: According to General Electric if the IoT can make oil and gas exploration and development even 1% more efficient it would result in a savings of $90 billion, reported.

5. It's not just a U.S. thing: As of summer 2014, a report from GSMA estimated that 27% of all machine-to-machine connections -- a form of the IoT -- are in China, while Europe had 29%, and the U.S. lagged behind at 19%.

6. What's the IoT?:  The world of connected devices has a long way to go. As of January, the majority of people, about 87% hadn't heard of the term "Internet of Things," according to Accenture.

7. The Internet is winning: Back in 2008, the number of devices connected to the Internet surpassed the number of people on Earth, according to Cisco

8. No, really, it's going to be very big: Research from McKinsey Global Institute examined more than 150 specific IoT applications that exist today or could be in widespread use within 10 years. The researchers found that total economic impact from the IoT could be between $3.9 trillion and $11.1 trillion by 2025. "We also found that more than two-thirds of value will be generated in business-to-business settings and that business customers and consumers will likely capture more than 90% of the value created," wrote McKinsey's James Manyika and Michael Chui of the research.