Making a low poly mesh look like a high poly mesh makes sense so I think I understand that one.
So if you have a complex node setup for a material, or a simple like a noise texture mixed with a checker texture etc, you connect them to the shader and then in the render options click bake? And then the result of those two textures are “forever” saved to an image that doesn’t have to be calculated by the shader several times? Cause now it just looks like a finished image? So when it comes time to render, Blender’s render engine looks at the baked file and not the material made in the shader editor, if that makes sense?
And if you need to bake like a normal map, would you do as in the picture? And then press baking in the render options, and then you would have baked a normal map? Or does it need to involve a texture?

Is this closer to understanding it? 🙂