Saturation and Vibrance both increase color intensity, but they do it differently.

• Saturation increases the saturation of all colors more evenly. It pushes every color stronger regardless of how saturated it already is, so it can make some areas look overdone.
• Vibrance is more selective. It increases less-saturated colors more than colors that are already strong, which usually gives a more balanced, natural-looking result.

In practice, Vibrance is often the safer adjustment when you want an image to look more colorful without clipping or overcooking areas that already have strong color. Saturation is better when you want a stronger overall effect and are okay with every color being affected equally.

A simple way to think of it:

• use vibrance for a subtle, natural boost
• use saturation for a stronger global color change