With the advancement of medical image processing along with computer-aided diagnosis approach, the existing healthcare system is equipped with potential imaging devices (e.g. CT scan, MRI, PET scan etc) that assist precise diagnosis of disease. Although, there is an availability of sophisticated radiological equipments, but sometimes identification of the disease becomes the most challenging task for the physician. This paper discusses mainly about the chest radiographic images and its associated problems that still remain as an open problem in research community. Chest radiographs are normally subjected for preprocessing, feature extraction, and then followed by classification. The paper discusses about the existing research technique for the detection and classification of the disease/abnormalities in chest radiographs. Finally a research gap is explored after reviewing the existing literatures.