This document provides an overview of artificial neural networks (ANNs). It begins with basic definitions of ANNs and their goal of modeling the human brain. It then discusses the structure of the human brain and early ANN models like the perceptron. The document outlines different ANN architectures including feed forward and feedback networks. It also covers learning methods in ANNs like supervised, unsupervised, and reinforcement learning. Applications of ANNs are then listed before the document concludes with a discussion of potential destructions if ANNs are not properly designed and controlled.