Altimeter

An altimeter is a tool that tells you how high above the ground you are. It's like a special watch, but instead of showing you the time, it shows you the height.

Think of it like this: when you're standing on the ground, you're at zero, right? But what if you climb up a mountain? Then you're higher than when you started, and the altimeter will show you that.

The way an altimeter works is by measuring air pressure. As you go higher and higher up, the air pressure decreases. The altimeter has a special sensor inside that can detect these changes in air pressure.

When you're flying on an airplane, the pilot uses the altimeter to help them know how high up they are. They need to know their altitude to navigate and to make sure they don't run into anything.

So, an altimeter basically tells you how high you are using air pressure, and can be used for navigation during flights.