Discuss the different techniques and best practices to secure a Node.js application.

Securing a Node.js application involves practices like input validation, using secure authentication mechanisms (e.g., JWT), and implementing proper session management. Regularly updating dependencies and using tools like npm audit can mitigate security risks.

Implementing HTTPS, employing security headers, and validating and sanitizing user inputs are crucial. Additionally, utilizing frameworks like Express with its security features and middleware, such as Helmet, can add an extra layer of protection against common vulnerabilities. Regular security audits and staying informed about the latest security practices are essential.