This chapter provides a general overview of digital camera components required in three-dimensional (3D) processing and labeling. The authors study each stage of light transport via the camera's optics, before light is captured as an image by the sensor and stored in a given format. They introduce the fundamentals of light transport as well as notations for wavelength and color spaces, commonly used in imaging. They examine how cameras have been adapted to capture and transform into digital image and describe the details of different components in a camera and their influence on the final image. In particular, they provide a overview of different optical components and sensors, examining their advantages and limitations. They investigate the link between camera models and the human visual system in terms of perception, optics and color fidelity. Finally, two current camera techniques, high-dynamic-range (HDR) and hyperspectral imaging, are explored.