A saw chain is like a necklace made up of little sharp teeth. Just like a real necklace, the saw chain wraps around in a circle. But instead of hugging your neck, it wraps around a round bar called a guide bar.
The teeth on the saw chain are like tiny knives that slice through wood when the chain spins around the guide bar. The guide bar helps the saw chain stay in the right position and keeps it from flying off.
Sometimes the saw chain gets dull or breaks, just like a pencil tip can get dull or break. When this happens, you need to sharpen the teeth or replace the chain altogether. Properly taking care of a saw chain helps it work better and last longer, just like keeping your toys in good condition helps them last longer too.