Securing an application and ensuring that the correct security is set up is important. Correct security entails making sure users are who they say they are (authentication). Correct security also entails proper authorization (that users can only access cases they are allowed to access and can only see data they are allowed to see. Correct security also means identifying and addressing security vulnerabilities like cross site scripting or phishing attacks. This module examines common mistakes that can open up vulnerabilities in the system, and how to address them to help avoid potential risks.