What is penetration?

Penetration is when something goes through another thing, like a toy going through a box.

Imagine you have a box full of marshmallows, and you use a toothpick to poke it. The toothpick goes right through the marshmallows, that's penetration! It’s like when you push your hand through a pillow, or when water goes through a sponge.

Think about a needle going into a balloon. At first, the balloon is whole and round. But as the needle moves in, it makes a small hole, that's penetration happening step by step. The more the needle pushes through, the bigger the hole gets.

Or think of a syringe: when you push the plunger, the medicine goes into your arm, that’s also penetration! It’s like something going through another thing to get to what's inside.