Gaussian blur is a widely used image processing technique that creates a smooth, blurred effect by averaging pixel values with their neighbors. The "Gaussian" part comes from using weights based on the Gaussian (normal) distribution, giving more importance to nearby pixels and less to distant ones. Here is a Gasussian Blur Wikipedia Link
At the heart of Gaussian blur is a "kernel" (also called a filter matrix). Think of it as a window that slides over your image. For beginners, start with a 3x3 matrix where: