The human gastrointestinal system can be affected by infections, inflammation and cancer. The most common disease of the gastrointestinal (GI) tract is gastroenteritis. Pathogens such as bacteria can induce gastroenteritis due to inflammation of the stomach and small intestine. The use of antibiotics reduces the microbiome diversity of the GI tract, which further aggravates the inflammatory response. Ileitis and colitis are two inflammatory conditions of the ileum and large intestine respectively. Appendicitis is the inflammation of the appendix, which can be potentially fatal if left untreated. Gastrointestinal cancer can also occur at different areas of the GI tract, such as esophageal cancer, colorectal cancer, tongue cancer, mouth cancer, stomach cancer, etc. The field of medicine concerned with the treatment and management of such disorders is known as gastroenterology. Various diagnostic and therapeutic procedures are inherent to the field of gastroenterology, such as endoscopic retrograde cholangiopancreatography, colonoscopy, endoscopy, liver biopsy, endoscopic ultrasound, etc. This book is a compilation of chapters that discuss the most vital concepts and emerging trends in the field of gastroenterology. It aims to shed light on some of the unexplored aspects of gastroenterology and the recent researches in this field. This book, with its detailed analyses and data, will prove immensely beneficial to professionals and students involved in this area at various levels.