The book "Histogram of Oriented Gradients" by Betascript Publishing provides a comprehensive introduction to histogram-oriented gradient (HOG) descriptors used in computer vision and image processing. This technique is crucial for object detection as it counts the frequency of gradient orientations in localized image areas. The method differs from other approaches by being based on a dense grid of evenly distributed cells and employing overlapping local contrast normalization to enhance performance. Originally introduced by Navneet Dalal and Bill Triggs in 2005, the research focused on pedestrian detection in static images but has since expanded to include the detection of people in film and video, as well as various animals and vehicles. This specialized book is a valuable resource for students and professionals interested in modern techniques of image processing and object detection.