Pathology is a medical science that studies the etiology, pathogenesis, morphological structure, function and metabolism of diseases with the method of natural science, and reveals the law of occurrence and development of diseases, so as to clarify the nature of diseases. Hematoxylin-eosin staining, HE staining for short. Hematoxylin dye solution is alkaline, which makes chromatin in the nucleus and ribosome in the cytoplasm purplish blue. Eosin is an acidic dye that mainly colors the cytoplasm and extracellular matrix components red. The properties that tend to be colored by alkaline or acidic dyes are called basophilic and acidophilic, respectively; If the affinity of the two dyes is not strong, it is called neutral. General tissue changes and tissue products can be shown by this staining method, which is the most commonly used staining method in morphology.