When you think of the Ringling Brothers, you probably think of trapeze artists, fire breathers and tigers jumping through hoops. Spies probably don't come to mind. But in fact, there was a time when the company synonymous with the circus ran its own spy agency. The reason they did it is truly shocking.

Wake up with Kim every Saturday morning! Grab a cup of coffee and catch up on top tech news, digital tips and how-tos, and highlights of Kim's show.

Every airport has its own specific three-letter code. Phoenix Sky Harbor Airport is PHX, for example, and Denver International Airport is DEN. It turns out that the way these codes are assigned is much more complicated than just abbreviating the city or state. If you fly to Montreal, Canada the call sign is YUL. Why is this and how does the system work?

What does it mean for something to be the color black? Simply put, it's when light cannot be reflected by an object. You might be surprised to learn that scientists have been searching for ways to create the blackest black in the world. It turns out super black paints can change the science world.

In 2013, the word "selfie" was added to the dictionary. It's defined as "a photograph that one has taken of oneself, typically one taken with a smartphone or webcam and shared via social media." But selfies existed long before 2013. The first selfie might be much older than you think.

I don’t trust Big Tech and you shouldn’t, either. You’ve heard me say for years that free email services like Gmail or Yahoo aren’t really free. There’s a big price to pay — your privacy. These free email sites scan, analyze and save details of every email you send and receive, giving Big Tech a very intimate and detailed profile of you so they can easily sell your data to the highest bidder.

That’s why I use StartMail. With StartMail, I can send encrypted emails with one click, even if the recipient doesn’t use encryption. And StartMail never scans or analyzes your emails. Best of all, when you delete an email, it’s gone — forever.