Chain codes are used to represent a boundary by a connected sequence of straight line segments. The representation is based on 4-connectivity and 8-connectivity of the segments. The chain code works best in binary images and is a concise way of representing a shape contour. As an edge is traced from its beginning point to end point, the direction that must be taken into consideration is to move from pixel to pixel in the given number present. Chain code is based on the idea that follow the outer edge of the object and the store of direction in which they are travelling.