What is the primary purpose of using masks in Photoshop?

The primary purpose of using masks in Photoshop is to hide portions of a layer. Masks provide a non-destructive way to control the visibility of different parts of a layer without permanently altering the original image or layer. This allows you to selectively reveal or conceal certain areas, enabling precise adjustments and creative effects. By using black on a mask, you can hide sections of the layer, and by using white, you can reveal them. This technique is fundamental in compositing images, making adjustments to specific areas, and creating complex visual compositions while maintaining full control over the original elements.

While creating new layers, increasing image resolution, and applying filters are important functions in Photoshop, they do not relate directly to the distinct feature and flexibility that masks provide in terms of controlling layer visibility. Masks are specifically designed for selective editing, which is a core aspect of advanced image manipulation.