Software testing is the process of verifying and validating software to identify defects and ensure it meets requirements and quality standards. Key content areas include understanding the testing process, different types of testing (like functional and non-functional, manual and automated), testing approaches (white-box, black-box, grey-box), and the Software Testing Life Cycle (STLC) which involves planning, execution, and reporting. The core goal is to find and fix bugs, which can range from functional issues to performance and security vulnerabilities.