Okay kiddo, so you know how you have a bunch of toys in your room and sometimes you want to play with certain toys together, right? Well, computers also have lots of toys they like to play with, except their toys are called "devices" like printers, phones, and other computers.
A network switch is like a toy organizer that helps the computers choose which toys they want to play with and where they want to play with them. It's like a traffic cop who directs cars on the road so they don't crash into each other.
So when a computer wants to play with a device, it sends a message to the network switch saying, "Hey, I want to talk to this device!" The network switch then checks to see where the device is located on the network and sends the message directly to that device.
This makes everything run more smoothly and quickly, because each message gets sent directly where it needs to go instead of the computer having to send messages to all devices one by one to hope it gets to the right one.
So basically, a network switch helps computers talk to devices without getting confused or running into each other, like an organizer in your room that helps you find your favorite toys quickly and easily.