The detection of sides and corners is useful and important in the shape perception of visual picture patterns. Similarly, the recognition of symmetry in pictures is helpful in reducing the storage space, in retrieving a missing portion, or in correcting the orientation of its shape. In the present paper, algorithms are found to detect the aides and symmetry of simply closed two-dimensional man-made and machine-generated outlines. A description based on the fuzzy set theoretic approach is also developed for imperfect non-geometric figures and results of the execution of the algorithms are presented.