This article discusses best practices for developing React applications with TypeScript, focusing on security concerns. It highlights the importance of strict mode in enforcing type constraints and catching type mismatch errors early. The article also warns about command injection attacks, HTML injections, and the use of opaque types to prevent duplicate values and ensure data integrity. Additionally, it emphasizes the need to sanitize user input when using `dangerouslySetInnerHTML` to prevent Cross-Site Scripting (XSS) attacks. By following these guidelines, developers can build fast and secure React applications with TypeScript.