According to the Harvard Business Review, almost 44 million American workers work a variety of side hustle jobs. These jobs range from renting out their homes, selling crafts online, or driving for ride-sharing companies.

One of the reasons side hustles are so popular is that they are an easy way to supplement your income. You can also feel like you're in charge of your work, leading you to become emotionally and cognitively invested. However, taking on a side hustle is not without complications. You don't want to take away from your full-time employment, so make sure you're balancing it with full-time work and other demands.

Four popular side hustle jobs that you could take on to increase your income include the following:

E-commerce. While this job is rather broad, e-commerce involves selling just about any item online. Turn your hobby into a profit by selling your crafts or collectibles. Some sites allow you to set up a store, or you can create a website where you list your items.

Party planning. You might have a knack for throwing parties that people talk about, so why not use that to our advantage and make it a side hustle? Maybe you love parties but don't like the idea of planning everything. If so, consider utilizing other talents and focus on being a DJ or catering.

Web design. If you have development or web design skills, you might be able to bring in some serious cash. Companies might be willing to work around your schedule if you have a full-time job or other responsibilities, so you can complete the work when it's convenient for you.

Photography. Maybe you're someone who enjoys taking pictures of your family and friends. If so, consider taking up photography as your side hustle. You can start small and offer to take family portraits and then work your way up to taking engagement or wedding photos.

While turning a passion into an additional career, side hustles can help you earn a little extra income. To determine which is the best side hustle for you, consider your skills and interests and determine how you can capitalize on them. Make sure you balance the time spent between your full-time gig and your side hustle so you don't end up burning out just to make additional money.

Sources: HBR.org, Thebalancecareers.com, Coursera.org