Okay kiddo, have you ever seen a toy that you wanted to buy but you weren't sure how it worked? A product demonstration is when someone shows you how a product works. It's like a teacher showing you how to do something new.
Let's take an example of a new toy car. The person doing the demonstration will take the toy car out of the box and show you how to play with it. They might show you how to make it go forward and backward, turn left and right, and maybe even show you how it can jump off ramps!
The person doing the demonstration will also explain how the toy works. They will tell you important information about the toy like how to charge the batteries, how long the batteries will last, and how to change the parts if they get broken.
Product demonstrations are very helpful because they teach you how to use a product before you buy it. It helps you make sure you are buying something that you will like and use.