What is the purpose of underpainting?

Underpainting serves as a foundational layer in the painting process, providing a base upon which subsequent layers of paint can be applied. This initial layer is typically completed with a monochromatic or neutral color and establishes the composition, structure, and tonal values of the artwork. By using underpainting, artists can work out the layout and shading before committing to the final colors, enhancing the overall coherence and depth of the piece.

While adding texture, mixing pigments, and protecting the canvas are interesting aspects of painting, they do not convey the primary purpose of underpainting as effectively as establishing a solid base for the layers to follow. Underpainting allows for greater control and refinement, making it a crucial step in many artists' workflows.