Hi there! Do you know what the internet is? It's like a big library where you can find information and different kinds of media like pictures, videos, music, and games. When you "download" something, it means you're taking a copy of that thing from the internet and saving it onto your own device, like a phone or computer.
Let's say you want to download a picture of a cute cartoon character. First, you have to find it on the internet. You might do this by searching for it on a search engine like Google. When you see the picture, you can click on a button that says "download" to save a copy of it onto your device.
Sometimes, downloading something can take a little while depending on how big the thing you're trying to download is and how fast your internet connection is. But once it's finished, you can enjoy it whenever you want without needing to be connected to the internet.
Just remember, downloading things can be a fun way to enjoy things on your own device, but it's important to make sure you're only downloading things that are safe and legal.