An excavator is a big machine that helps to dig and move dirt. Imagine a big robot that has a huge bucket on the front, just like a big scoop! This bucket can pick up lots of dirt and heavy things. It works like when you use a shovel to move sand in a sandbox. But this machine is much stronger and can move more dirt than we can with our hands. The excavator can help build roads and houses by digging holes. Isn't it cool to see how it moves the dirt around?