Your heart is like a little pump inside your body that helps move blood around. When your heart pumps, it makes different sounds that can be heard with a special tool called a stethoscope.
The main sounds your heart makes when it pumps are called "lub" and "dub." Imagine your heart as a little person with two doors inside. When the first door opens, it makes a "lub" sound. That's when your heart is filling up with blood. Then the second door opens and it makes a "dub" sound. That's when your heart is pushing the blood out into your body.
When a doctor listens to your heart with a stethoscope, they can hear if your heart sounds normal or if there are any problems. Sometimes your heart might make extra sounds or "whooshing" sounds which can mean there's something wrong.
It's important to visit the doctor and have them listen to your heart to make sure it's healthy and making the right sounds.