Back Propagation
Back propagation is how a neural network learns from its mistakes by tracing each error back through its layers to adjust.
Think of it this way
A cook bakes a cake and finds it too salty. She traces the salt back through each step: the frosting, the batter, the dry mix. At each layer, she notes how much salt went in and adjusts that amount down. Each step gets a small fix based on how much it added to the final mistake.
Explaining back propagation by grade level
Think of a brain that reads numbers. It guesses what digit it sees. When it gets one wrong, it goes back step by step. It fixes each part so the next guess is better.
