Clerk offers a full-stack authentication and user management system designed for modern web applications. It provides secure APIs and drop-in UI components for sign-up, sign-in, user profiles, multi-factor authentication (MFA), and organization management. Clerk supports frameworks like Next.js, React, Vue, and Nuxt, with built-in OAuth, SSO, and RBAC (Role-Based Access Control). Focused on developer experience, Clerk eliminates the need to build authentication from scratch, ensuring security and scalability without sacrificing flexibility or control.