Linked from
The 10 pages that link to Gas pressure, each with the reason it gives.
Gravitational collapseRelated: Thermal gas pressure can oppose gravity in a collapsing cloud.
GasRelated: Molecular collisions with container walls create the pressure characteristic of gases.
Tennis ballRelated: Internal pressure affects how the hollow ball deforms and rebounds.
Paschen's lawRelated: It is one factor in the pressure–spacing product governing breakdown voltage.