It's not exactly easy money, but there are ways to earn some cash by submitting your photos to stock photography services. Here's how to get started.

Photography is not an easy job. Capturing the best shots takes not only skill but sometimes bravery and some innate artistic talent.
Yet smartphones have made everyone think they're a photographer these days. So it's entirely possible that the shots you take on that smartphone (or with your digital camera of choice) could put a little money in your pocket, whether you consider yourself a pro-photog or not.
I'm not talking about active photography jobs like shooting weddings, sports, food, fashion, babies, or pictures of tech products. Leave that to the pros. I'm talking about passive income, where you monetarily benefit from digital pictures that would otherwise just be taking up space on a digital drive. The best way to do that: sell your images as stock photography.

What Is Stock Photography?

Since the 1920s, stock photography has been around to provide photos for all sorts of media: print publications, websites, newsletters, you name it. Generally, the person who publishes the photo pays a fee for a license to use the image, be it a few cents or several hundred dollars. It was a lot cheaper than having photographers on staff back in the day, with all the overhead they'd need for developing photos. (Unlike today when you take a shot and can edit it in seconds.)
Publishers used to find images in catalogs, then on CDs; now all the stock photography providers are online.
While there are a few major stock photography outlets—Getty Images is the 800-pound gorilla in this space—there are also plenty of what's called microstockoutlets. These sites are hungry for new content that meets its needs, and that's where you come in. A microstock agency that accepts images you offer would then market those images in its database, and if anyone wants to use it, they have to pay the agency. You get a share of that—sometimes a hefty share, if the terms are right.
Remember this is passive income. It's not all that passive up front, considering the work it takes to upload images to sites with all the right metadata. You have to send them one image at a time with all the information that's pertinent. And if you're going to be successful, the more images you offer (that get accepted) the better. But you can't count on making money quick.
Are you going to make millions? Unlikely, unless you're the best of the best, in which case you'd be doing gallery openings and shooting magazine covers. You probably won't even make enough for coffee once a month. But sometimes people get lucky with a single shot.
The co-founder of Photerloo (a site for uploading your images to multiple sites at once) uploaded some pics a few years ago and started making $100 a month, with one pic, in particular, garnering $4,000 by itself. But that took 6,000 licenses of that image across five different microstock sites to reach that amount because licensers only spend around $0.20 to $5 to use the shot.
You won't know if you have similar luck until you do the work of uploading some shots.