Refresh tokens are essential components in authentication processes, particularly within the OAuth 2.0 and OpenID Connect protocols, serving as long-lived counterparts to short-lived access tokens. They allow users to maintain continuous access to applications without frequently logging in, enhancing both security and user experience by minimizing the risk of access token theft and reducing latency. Typically appearing as random strings, refresh tokens are used to generate new access tokens once the original expires, without requiring re-authentication. Their implementation requires secure storage, a rotation policy to mitigate theft risks, and a revocation mechanism for scenarios like user logout or password change. They are particularly useful for maintaining long-lived sessions in mobile, desktop, and single-page applications, as well as enabling background processes and third-party access. Understanding and properly implementing refresh tokens can significantly improve application security and usability, and platforms like Descope offer tools to integrate these processes with ease.