This lecture introduces convolutional neural networks, focusing on their application in image and audio signal processing. It covers the concept of convolution, different types of filters used in signal processing, and how convolution is applied to both discrete and continuous signals. The lecture also discusses the importance of preserving spatial structures in images and the role of convolution in reducing the dimensionality of input data. Additionally, it explores various filter operations such as averaging, sharpening, smoothing, and derivative approximation, showcasing their impact on signal processing. The session concludes with a brief overview of extending convolution to 2D for image analysis and its role in neural networks.