# What is PSI Pressure?

PSI, or pounds per square inch, is a way to measure pressure. Pressure tells us how much force is pushing on something. Think about blowing up a balloon. The air you blow into the balloon pushes against the inside of it. The more air you add, the harder it pushes, and the tighter the balloon gets. This pushing force inside the balloon is called pressure.

Now, PSI is a special unit we use to say how strong that push is. If you imagine a square inch, which is about the size of a small postage stamp, PSI tells us how much force is pushing on that tiny area. For example, if you press your finger on a scale and it shows 2 PSI, that means you’re pushing with 2 pounds of force on every square inch of the scale.

PSI is important in many everyday things, like car tires. If you’ve ever seen someone check the tire pressure, they’re looking at the PSI. If the PSI is too low, the tire might be flat; if it’s too high, the tire could burst. That’s why it’s important to have the right PSI.