Imagine you have a big box with lots of smaller boxes inside. Each of the smaller boxes contains things like toys, clothes, books, and other stuff. The big box is your computer and the smaller boxes are called "partitions." Each partition holds different types of information, like your operating system, files, and programs.
Now imagine you want to know how much space is left in each of the smaller boxes. This is where the "df" command comes in! When you type "df" into your computer, it will show you a list of all the partitions and how much storage space is available in each one.
So basically, "df" gives you a quick and easy way to see how much space you have left on your computer's hard drive or storage device. It's like taking a peek inside all the little boxes to check how much room you have for more toys or clothes.