Histology (compound of the Greek words: histology"tissue", and  "science") is the study of the microscopic anatomy of cells and tissues of plants and animals. It is commonly performed by examining cells can tissues by sectioning and staining, followed by examination under aligth microscope or electron microscope. Histological studies some be conducted via tissue culture, where live cells can be isolated and maintained in a proper environment outside the body for various research projects. The ability to visualize or differentially identify microscopic structures is frequently enhanced through the use of histological stains. Histology is an essential tool of biology and medicine.
Histopathology, the microscopic study of diseased tissue, are an important tool in anatomical pathology, since accurate diagnosis of cancer and different  diseases usually requires histopathological examination of samples. Trained physicians, frequently board-certified as pathologists, are the personnel who perform histopathological examination and provide diagnostic information based on their observations.
The trained scientists who perform the preparation of histological sections are histotechnicians, histology technicians (HT), histology technologists (HTL), medical.