Retina (part of the eye) stained with hematoxylin and eosin, cell nuclei stained blue-purple and extracellular material stained pink. Hematoxylin and eosin stain (or haematoxylin and eosin stain or hematoxylin-eosin stain; often abbreviated as<unk>  or<unk>  is one of the principal tissue stains used in histology. It is the most widely used stain in medical diagnosis and is often the gold standard. For example, when a pathologist looks at a biopsy of a suspected cancer, the histological section is likely to be stained with H&E. H&E is the combination of two histological stains: hematoxylin and eosin. The hematoxylin stains cell nuclei a purplish blue, and eosin stains the extracellular matrix and cytoplasm pink, with other structures taking on different shades, hues, and combinations of these colors. Hence a pathologist can easily differentiate between the nuclear and cytoplasmic parts of a cell, and additionally, the overall patterns of coloration from the stain show the general layout and distribution of cells and provides a general overview of a tissue sample's structure. Thus, pattern recognition, both by expert humans themselves and by software that aids those experts (in digital pathology), provides histologic information. This stain combination was first introduced in 1876 by A. Wissowzky.
H&E stain
HPS stain
Giemsa stain
PAS diastase stain
Leishman stain
Phosphotungstic acid-haematoxylin stain
Mucicarmine stain
Auramine phenol stain