Data hierarchy

Data hierarchy is like a pyramid that tells you what type of data is most important to least important. Think of it like how you might stack blocks. At the top is the most important data, like your name or address. Then the next layer down is slightly less important data, like your favorite color. And so on until you reach the bottom layer which is the least important data - like what color socks you are wearing today. Each layer has some data that is more important than the one beneath it, just like the blocks in your pyramid.