Gibbs phenomenon

Gibbs phenomenon is a strange thing that happens when you try to make something smooth with math. It's like when you try to draw a straight line with your finger on the steamy window of a shower. Instead of making one smooth line, your finger leaves bumpy, jagged peaks and valleys. That's the Gibbs phenomenon. It's when you try to make something smooth using math, but instead of a nice flat surface it leaves jagged edges.