Hexagonal structure is a different approach to represent an image rather than the traditional square structure. The arrangement of photo receptors in HVS is similar to hexagonal structure. So, if we are able to represent images using hexagonal structure, the computer vision will be as close to human vision. Since there is no hardware available at present to acquire hexagonal images, we have to simulate hexagonal grid on a square pixel image for processing the images in hexagonal domain. This book gives an idea of pseudo hexagonal structure image and provide an algorithm for generating a pseudo hexagonal image. An image steganography method using pseudo hexagonal image as cover image is also described in this book.