Pathology is a broad field which is divided into specialisations and sub-specialisations, and bridges knowledge between clinical medicine and science. It is considered the foundation of testing, treatment and patient care. Pathology studies biology and microbiology, and molecular/genetic pathology. Specialties and sub-specialties include histopathology (surgical pathology), medical microbiology, cytopathology, chemical pathology, haematology, immunology, and other Cellular Pathology Specialties (Diagnostic neuropathology, Paediatric and perinatal pathology, and Forensic histopathology). Pathology practice involves many diagnostic techniques, including examination of the patient, taking specimens of blood, tissue or fluids, and conducting tests, investigations, and laboratory operations. It seeks to use safe and accurate procedures which produce high-quality material and interpretation. This field of medicine recognises the diagnostic value of individual tests, while being aware of the limitations of investigations and knowledge. It contributes expert opinion to other specialty areas of medicine and science, as well as pathology research and education.