Patients or family members who come to the pathology department for the first time often know nothing about pathology and always ask the same question, “What is pathology for?” We always patiently explain as much as we can to them when we have time. Although pathology is the foundation and bridge of medicine in the medical curriculum, as a clinical diagnosis she has also been with Western medicine throughout its development. Although many aspects of medicine have now developed to very sophisticated technology, pathology is no exception, but pathological diagnosis since the application of clinical as an important diagnostic method, but still ordinary light microscopic observation as the main diagnostic method, because the direct observation of tissue by light microscopy is the most direct reflection of the disease, with the development of science, researchers on human tissue continue to find new markers or genetic changes, as With the development of science, researchers continue to discover new markers or genetic changes in human tissues, and as an auxiliary method of pathological diagnosis is also continuously applied in clinical practice. At present, the main content of pathological examination is still the “section examination” of human tissue lesions (such as body surface or visceral swelling after excision or gastroscopy and other instruments to remove lesions in the gastrointestinal tissues, etc.) and the “smear examination” of human exfoliated cells (such as sputum, pleural fluid, cervical cells, etc.). After careful observation of the above tissues and cells, the diagnosis and classification of benign and malignant lesions can be clarified, and pathological diagnosis is the most accurate of all diagnostic methods at present.