Neural Network
A computing system loosely inspired by the brain that learns patterns from data.
A neural network is a system of layers of mathematical functions — called neurons — that transform input data into output predictions. Each neuron takes in numbers, applies a calculation, and passes the result to the next layer. During training, the network adjusts millions of these calculations until its outputs match the desired results.
Think of a factory assembly line where each station does one small transformation to a product. Raw materials go in one end, finished product comes out the other. A neural network works the same way — raw data goes in, passes through many transformation stations, and a prediction comes out. Training is the process of fine-tuning what each station does until the output is reliably correct.
Neural networks are not modelled on the brain in any meaningful technical sense. The term "neuron" is a loose metaphor from the 1940s that stuck. Modern neural networks share almost nothing with biological neurons — they are optimised mathematical functions, not simulations of brain tissue.