Do you know what a magnet is? It's something that attracts other things made of metal, right? Well, if you have a charged object (something with too many or too few electric particles in it) it can also attract or repel other charged objects.
Now imagine if you had a big charged object and you wanted to figure out how it would affect the space around it. That's where the electric displacement field comes in. It's like a map that shows how the charged object will affect the space around it.
But how does it work? Imagine you have a lot of little balls all together, and you want to put another ball in the middle. If the balls are really close together, it will be harder to push that new ball in. And if there are already a lot of balls in one spot, it will even try to push the new ball back out.
The same thing happens with the electric displacement field. If there are already a lot of electric particles in one spot, it will try to push new charged objects away. And if there aren't many charged objects in one spot, the new ones will be more easily pushed in.
So the electric displacement field helps us understand how charged objects affect the space around them. And just like a map, it can help us predict what will happen before it happens.