A hanging strap is a long, thin piece of strong material that you can use to hang things up. It's kind of like a big, long noodle that you can wrap around something and then hang from a hook or nail.
Imagine if you have a heavy bag of toys that you want to hang up in your closet. You can't just put it on a shelf because it's too heavy and might fall off. But if you have a hanging strap, you can wrap it around the bag and then hang the strap from a hook or hanger in your closet.
Hanging straps are really useful for all kinds of things, like hanging up clothes or towels, or hanging plants from your ceiling. And they're really strong, so you don't have to worry about things falling down. Just make sure you tie them tightly, so they don't slip!