What are paper cuts ( i know that they are cuts that you get from paper) but why do they occur?

The problem arises when there's enough pressure on the paper to cut the skin. Most commonly, paper cuts are caused by sheets of paper that are bundled together with one sheet being dislodged from the rest. The other sheets hold the loose one in position, causing it to act like a razor blade and slice your skin.

When there is enough pressure on the paper and the skin

Explanation:

clean the wound to make sure of no infections.