Post effects (or PostFx) are usually applied to the rendered scene image but before UI drawing. You can use post-effects to establish look of your scenes and add more realism to them.
- Ambient Occlusion
- Anti-Aliasing
- Bloom
- Camera Artifacts
- Color Grading
- Depth of Field
- Motion Blur
- Eye Adaptation
- Lens Flares
- Screen Space Reflections
- Tone Mapping
- PostFx Volumes
- PostFx Materials
As you can see in a picture below using postFx can dramatically change look of the game.