Your electrical panel functions as the entry point for electricity into your home. After the power reaches your electrical panel from the utility company, it flows out into the various circuits of your home until it eventually reaches your appliances and other electrical devices.
When too much power flows through a wire, it can cause overheating and melting. This can lead to fire. If you were to ever touch a wire that is overloaded, you could even be shocked. Your breaker panel is designed to sense when there is too much electricity flowing through a particular circuit, and shut off power to that area of your home. If you have an older electrical panel, this will cause a fuse to blow. In newer breaker panels, a breaker will trip.