Introduction: The lines between non-invasive medical treatments and invasive surgical treatments meet at therapeutic endoscopy.Advances in endoscopic practice are challenging traditional views on how neoplasia should be managed in the gastrointestinal system. Identifying pre-malignant changes in the gut is central to successful early management of most cancers. There has been rapid growth in the equipment and technology available for evaluating potentially neoplastic lesions in the gastrointestinal tract.Not only tumors have gotten the premium interest but also non oncologic diseases were also involved. The model of an endoscopist has changed in the last 10 years. Nowadays, the endoscopist has to be skillful not only in using standard endoscopes and macroscopic view of the lesions in the gut but with good experience in ultrasound, pathology and physics. Since 1961, the conventional white light fiber endoscopes have been and still mainly used for the diagnosis of mucosal lesions with the ability of many diagnostic and therapeutic interventions. However, nodetailed information can be obtained about the mural layers of the gut and extramural organs.