What is geyser?

A geyser is like a special kind of fountain that shoots hot water and steam high into the air, just like when you open the tap on a very full kettle.

Imagine there's a big underground lake filled with hot water. Sometimes, this water gets so hot it turns into steam, kind of like how your soup bubbles up when it’s boiling. This steam pushes the hot water up through a pipe-like hole in the ground, and boom! It sprays out like a fountain.

Think about filling a balloon with air, as you blow more air in, the balloon gets bigger and tighter. A geyser is kind of like that balloon. The hot water and steam build up pressure underground until it's too tight, and whoosh! It all comes out at once.

Some geysers do this every few hours or even every day, just like how you might brush your teeth at the same time every morning. One of the most famous ones is called Old Faithful, because it usually goes off right on time!

So a geyser is like an underground hot water fountain that shoots up in bursts, and some of them are super reliable, just like your favorite bedtime story!