The purpose of this book is to introduce the reader to the different types of image file formats and their processing, and to present an application based on a technique of image search called content-based image retrieval. The application uses Google to retrieve results that are similar to an original image. The application searches for similar images by comparing the colour composition of regions in the template image to the colour composition of regions in the candidate image. The purpose of the application is to be used as an aid for the Google search engine.