Okay kiddo, have you ever heard of a car? Well, a jack of speed is a tool that helps you work on cars. Sometimes, you need to fix or change the tires on a car. And when you do this, you need to lift the car up so you can reach the tires. But lifting a car is really heavy and hard to do by yourself. This is where a jack of speed comes in. It's a special tool that you can use to lift up the car so you can change the tires. Just like how you might use a stool to reach something high up, the jack of speed helps you reach the tires on a car. But, you have to be very careful when using it because lifting a car can be dangerous. So, let's make sure that you always ask an adult for help when using a jack of speed.