DAST (Dynamic Application Security Testing) is a cybersecurity technique used to identify vulnerabilities in web applications while they are running. Unlike static testing, which analyzes source code, DAST interacts with the application in real time, simulating attacks to detect security flaws such as SQL injection, cross-site scripting (XSS), and other exploitable issues. This method does not require access to the source code, making it suitable for testing third-party applications or those with inaccessible codebases. DAST tools crawl the application's interface, sending various inputs and monitoring outputs to uncover weaknesses that could be exploited by attackers. It is an essential part of a comprehensive security strategy, complementing other testing methods to ensure robust application security.