ELI5: Explain Like I'm 5

Complementary goods

Complementary goods are items that are used together or go well together. Kind of like how macaroni and cheese is delicious by itself, but it's even better when you add ketchup or hot dogs to it! These additional items make the macaroni and cheese even more enjoyable.

In simple terms, complementary goods are things that are better when they are used together. When you have one of these items, you might want or need the other one too. For example, if you have a bicycle, you might also want to buy a helmet to keep you safe while biking. The helmet is the complementary good because it complements or completes the bike-riding experience.

Other examples of complementary goods include a computer and software, a printer and ink, or a phone and a phone case. These things work even better together than they do alone. So, when you see a complementary good for sale, it might be a good idea to consider getting it to enhance your overall experience with the item you already have.