Gel Doc is a piece of laboratory equipment used to capture and analyze images of DNA, RNA, and protein gels. It is an essential tool in molecular biology research and is widely used in various applications, such as Western blotting, Southern blotting, and gel electrophoresis. The Gel Doc typically consists of a darkroom, a camera, a computer, and imaging software. The gel is placed on a transilluminator in the darkroom, and the camera captures an image of the gel. The image is then displayed on the computer screen and can be analyzed and manipulated using specialized software. Some Gel Doc systems also have a UV light source for excitation of fluorescent dyes used in DNA and protein detection. Gel Doc is essential in the detection and analysis of nucleic acids and proteins and has been instrumental in advancing our understanding of molecular biology.