Okay kiddo, you know how sometimes when you're talking to someone on the phone, you can hear other noises in the background like people talking or cars driving by? Well, the internet can have background noise too!
When we use the internet, we are sending and receiving lots of information through wires and cables. Sometimes, as that information travels through those wires, it can pick up extra little bits of information or "noise" along the way. This is kind of like when you're trying to have a conversation with someone but someone else is talking loudly nearby and it makes it harder to hear the person you're talking to.
Although this internet background noise can be frustrating sometimes because it can slow down our internet connection, there are things that people who work with the internet can do to try to get rid of it and make our internet experience smoother. So, just like we can try to tune out background noise when we're on the phone, the internet tries to filter out its background noise too!