Gastrascopy, commonly referred to as gastroscopy, is a medical procedure used to examine the inner lining of the stomach and the upper part of the small intestine. It involves the use of a flexible tube called an endoscope, which is equipped with a camera and light source, allowing doctors to visualize and diagnose conditions such as ulcers, inflammation, or tumors. The procedure is typically performed under sedation and can also be used to take biopsies for further analysis.