The PSD file format is the native file format for Adobe Photoshop. It's a proprietary layered image file format that allows users to save images with multiple layers, including text layers, adjustment layers, masks, and effects. This makes it a highly versatile format for complex image editing and manipulation. PSD files retain all the editing information, allowing users to go back and modify individual layers or effects at any time. This non-destructive editing capability is a key feature. PSD files can also store large images with high color depth and resolution, making them suitable for professional-quality graphics and designs. While PSD files are primarily associated with Photoshop, other Adobe applications like Illustrator and Premiere Pro can also interact with them. The format supports various color modes, including RGB, CMYK, Grayscale, and Indexed Color. PSD files are generally larger in size compared to flattened image formats like JPEG or PNG because they store all the layer data. When sharing images for viewing or printing, it's common to export a flattened version of the PSD file to a more widely compatible format.