This document provides an overview of neural networks and deep learning. It describes how artificial neurons are arranged in layers to form feedforward neural networks, with information fed from the input layer to subsequent hidden and output layers. Networks are trained using gradient descent to adjust weights between layers to minimize error. Convolutional neural networks are also discussed, which apply convolution and pooling operations to process visual inputs like images for tasks such as image classification. CNNs have achieved success in applications involving computer vision, natural language processing, and more.