Most Internet users know the cloud as a place where files are stored digitally instead of on a physical device, like a computer’s hard drive, but what exactly does it look like? Despite the nickname, the cloud is not a mass in the sky. Cloud computing providers have large server rooms (or “farms”), like the one above, which hold your data so you don’t have to.

From the outside, the farms are not that exciting architecturally, but the interiors are mazes of incredible amounts of data. Like massive libraries that stock electronics instead of books, these farms contain row after row of blinking server racks with cables connecting them, as seen in the video above from CNN Money. Those racks are flanked by cooling systems because servers run hot, especially when there are thousands of them in an enclosed space.

The data centers used by some of the biggest companies—Facebook, Google, and Apple—are scattered across the world. One of Facebook's farms sits atop a hill in the small town of Prineville, Oregon and spans 147,000 square feet. Apple has a 200-acre data center located in North Carolina, where the company also built the nation's largest privately owned solar farm to run it (data centers use an estimated two percent of the country's electricity).

Curious about where Google Cloud lives? Check out the company's website, which shows exactly where its data centers are located—including St. Ghislain, Belgium; Changhua County, Taiwan; and Council Bluffs, Iowa—and how they are used.

According to CNN Money, 320 million people use iCloud—the cloud computing service launched by Apple in 2011—and over 400 billion Facebook photos are housed in cloud storage, with an additional 350 million added every day. To keep up with the growing demand, more companies are investing heavily in the cloud and server farms are getting larger. In fact, some predict that by 2020, the cloud will be a $191 billion market (up from the $100 billion the industry is currently worth, according to CNN Money.)

While there is nothing fluffy about the hardware that makes the cloud possible, it does owe its name to the sun-blockers above. The term “the cloud” is believed to stem from a patent filed in 1994 for a “network having secure fast packet switching and guaranteed quality of service,” in which the authors included a diagram of the system with a bubble around the “network.” As the patents evolved, the crude bubble shape became more like cloud-like, and according to Technology Review, “cloud computing” was first used in a 1996 business plan for the Compaq computer company. Check out the video from CNN Money for more about what the cloud looks like.

[h/t: CNN Money]

Header image via iStock.