Hierarchy in graphic design refers to the arrangement of graphic elements in a design in order of importance of each element. It is a principle of visual design that helps designers structure visual characteristics, such as size, color, contrast, alignment, repetition, and brightness, to emphasize certain characteristics of the design. The concept of visual hierarchy is based on Gestalt psychology, which proposes that the human brain has innate organizing tendencies that structure individual elements, shapes, or forms into a coherent, organized whole, especially when processing visual information.

Designers use hierarchy to guide the eye to information in a specific order for a specific purpose. By manipulating hierarchy in graphic design, designers can show how the elements of their piece interact together, calling attention to the most important elements and minimizing the focus on other, less-critical elements of the design. Establishing clear visual hierarchy is important because it holds a design together and can make a complex message simple.

In summary, hierarchy in graphic design is a set of principles that influence the order in which we notice what we see. It is used to add structure, create visual organization, create direction, add emphasis, and help a viewer navigate and digest information easily.