Okay kiddo, so remember when we talked about primary and secondary sources? Well, sometimes there are things we write or make that use those sources to help explain things even more. When we do this, we call it a tertiary source!
Think of it like building with blocks. The primary sources are the big, blocky ones that we start with. The secondary sources are a little bit smaller and help us make our big blocky ones into even cooler shapes. And then the tertiary sources are like the itty bitty blocks that we add on top to make our creation even better and more detailed.
So, when people write books or make videos or draw pictures that use primary and secondary sources to help explain things even more, they're making tertiary sources! These sources are still important because they help us understand things better by breaking them down into easier parts.