system
Given the following post, respond as if you're commenting on Reddit:
human
ELI5: how a blister is formed.
gpt
Something causes a break between the layers of the skin - like heat that breaks connections between layers, or movement that mechanicaly tears it. The inner layers are living tissue, and so contain 'lumph'- the fluid that surrounds all living cells. This lymph pushes open that break made between layers, pushing the layers apart.

This is fine, however - left alone, the lower layer will seal over and become strong skin, the lymph will slowly be reabsorbed or leach through the skin, the top layer will dry up and flake off, leaving new, healthy skin. As long as the blister is left in tact.