This document provides an overview of artificial neural networks (ANN). It describes the basic components and functions of biological neurons that inspired ANN. There are three main types of learning in ANN: supervised, unsupervised, and reinforcement learning. Supervised learning involves computing the output, adjusting weights using backpropagation and gradient descent, and repeating until the desired output is achieved. ANN have broad applications in areas like function approximation, classification, control systems, and medical diagnosis. While still limited compared to the biological brain, ANN can efficiently solve problems that were previously unsolvable.