Manual testing is the process of manually executing test cases without using automation tools. Testers simulate end-user scenarios to identify bugs, ensure functionality, and verify compliance with requirements. It is essential for exploratory, usability, and ad-hoc testing.
Automation testing uses scripts and testing tools to automate test execution, improving efficiency and accuracy. It is ideal for repetitive tasks, regression testing, and performance testing, ensuring faster and more reliable results. Common tools include Selenium, JUnit, and TestNG.