Well, kiddo, the International Hydrological Programme, or IHP for short, is an international program that helps people study and better understand water.
You see, water is super important for life on Earth. We need it to drink, grow crops, and keep our environment healthy. But sometimes, there can be too much water, like when there are floods, or not enough water, like when there are droughts.
That's where the IHP comes in. They have special scientists and experts who study water and how it flows through the environment (like rivers and lakes). They look at things like how much water is available, how it's being used, and how climate change affects it all.
Then, they share all of this information with people all over the world so that we can make better decisions about how to manage our water resources. That way, we can keep our planet healthy for a long, long time!