The ColorCorrectionEffect can be used to adjust several color-related properties at once: Saturation, TintColor, Brightness and Contrast. It's useful for fine-tuning the visual aesthetic of a world or communicating status effects to the player. Multiple ColorCorrectionEffect objects can be applied at once and they will compose their effects together.
Like other post-processing effects, ColorCorrectionEffect will only work while Enabled and when parented to Lighting or Workspace.CurrentCamera. Also, it may render differently depending on your Studio settings (see the Quality Level settings in Rendering → Performance).
For more details on this effect and others, see Post-Processing Effects.