What purpose do blending modes serve in Photoshop?

Blending modes in Photoshop are essential for defining how a layer interacts with the layers beneath it. Each blending mode alters the way the pixels of the active layer blend with those of the layers below, resulting in various visual effects. For instance, using the "Multiply" blending mode causes the colors of the active layer to darken the colors of the layers underneath, effectively creating shadows. Conversely, modes like "Screen" lighten the underlying layers.

This functionality allows for creative possibilities such as adjusting the overall look and feel of an image, applying textures, or enhancing colors without needing to directly modify the original layers. Since blending modes can transform how colors and tones are perceived, they are a powerful tool that enhances creative expression in digital design.

In contrast, other options do not accurately describe the role of blending modes. Enhancing resolution pertains to image quality and size, and is not achieved through blending modes. Creating new layer types is a function associated with layer management and properties, which is distinct from blending interactions. Changing the image file format relates to saving and exporting files, which does not involve blending modes at all. Thus, the correct understanding of blending modes is fundamental to utilizing Photoshop effectively for image manipulation.