Helicobacter pylori, a gram-negative bacterium is a common infection in the developing world. The discovery of H. pylori has been associated with gastric problems and, in severe cases, gastric cancer. Across the world, millions of people are suffering from peptic ulcer, which may progress to gastric cancer. The pathogen is generally transmitted through contaminated food and water sources or from an infected person to others. The prevalence of H. pylori infections arises chiefly in developing countries, because many of these countries suffer extremely from a test and treatment approach.This book details the pathophysiology, symptoms, complications, and treatment of H. pylori, and will address the need of students and healthcare workers who want to learn more about this subject. It covers the brief history, taxonomy and virulence factors of H. pylori, as well as its mechanism of transmission, pathogenicity, resistance, isolation, culturing, and possible treatment.