The chapter introduces the field of Three-Dimensional (3D) Computer Vision, detailing its historical development and key research areas. It covers related fields such as image processing, pattern recognition, and computer graphics. The mainstream of 3D computer vision research is traced from pioneering work to the use of physics and Marr's theory of human vision. The chapter also discusses various aspects of image input, including imaging geometry, input devices, color representation, and range data processing. It delves into image feature extraction methods, such as edge detection, edge linking, and region methods. The interpretation of line drawings and the realizability of line drawings are explored, along with stereo vision and shape from monocular images. The chapter further examines range data processing, scene segmentation, and the construction of surface elements. It concludes with discussions on knowledge representation and use, image analysis using scene knowledge, and image understanding using two-dimensional and three-dimensional models.The chapter introduces the field of Three-Dimensional (3D) Computer Vision, detailing its historical development and key research areas. It covers related fields such as image processing, pattern recognition, and computer graphics. The mainstream of 3D computer vision research is traced from pioneering work to the use of physics and Marr's theory of human vision. The chapter also discusses various aspects of image input, including imaging geometry, input devices, color representation, and range data processing. It delves into image feature extraction methods, such as edge detection, edge linking, and region methods. The interpretation of line drawings and the realizability of line drawings are explored, along with stereo vision and shape from monocular images. The chapter further examines range data processing, scene segmentation, and the construction of surface elements. It concludes with discussions on knowledge representation and use, image analysis using scene knowledge, and image understanding using two-dimensional and three-dimensional models.