In design software, what does "flattening" an image mean?

Flattening an image refers to the process of merging multiple layers into a single layer, thus simplifying the image's structure. This is commonly done in graphic design software when the designer wants to finalize artwork by consolidating all edits, effects, and adjustments into one flat layer. This ensures that the image can be easily saved, exported, or printed without losing any visual fidelity, as it removes the complexity of having multiple layers that may be editable but could complicate the rendering process. This action is particularly useful when preparing images for publication or further use in other applications that may not support layered files.

Creating a new layer, changing the resolution, or applying a color gradient does not involve the merging of multiple layers into one and is not aligned with the definition of flattening in the context of graphic design.