Software testing is the process of checking an application to confirm it works as intended, meets requirements, and is free of defects before release. It includes manual, automation, performance, security, and regression testing, each catching different kinds of problems. Strong testing lowers fixing costs and builds confidence in every release. For those starting a quality assurance career, a Software Testing Course in Chennai at FITA Academy offers hands-on training in test design, defect management, automation tools like Selenium, and placement support.