Pressure exerted by gas is called gas pressure.
I other words we can say that pressure is a force exerted by the substance per unit area on another substance.
The pressure of a gas is the force that the gas exerts on the walls of its container.
When we blow air into a balloon, the balloon expands because the pressure of air molecules is greater on the inside of the balloon than the outside.If we blow increase the amount of the pressure into a balloon, possibly it raptures because its walls are not strong enough to hold the pressure of air.
You must remember pressure always exert force.
Pressure = Force / Area .