What are the different sandpaper grits available for sanding various surfaces?

Sandpaper grits range from coarse (around 40-60 grit) for heavy sanding and removing material, to medium (around 80-120 grit) for general sanding, and fine (around 150-240 grit) for smoothing and finishing surfaces. Ultra-fine grits (above 240) are used for polishing and achieving a very smooth finish.