Cell relay is like a mailman who delivers letters. In this case, the letters are called "packets" and they have information inside them. The mailman is called the "switch" and he delivers the packets to their destination.
But instead of sending whole letters, the packets are broken up into smaller pieces called "cells." The cells are like puzzle pieces that fit together to make the whole picture.
Each cell has information about where it's going and what piece of information it has. The switch reads this information to know where to send each cell.
This is helpful because it makes it easier to send a lot of information at once. The switch can quickly sort the cells and send them to their destination.
Think of it like a conveyor belt at a factory. The cells are like boxes of parts going down the belt. The switch is like the machine that moves the boxes to the right place on the belt. In the end, the parts are all put together to make something cool!