OAuth is an open, token-based authorization framework that allows users to grant third-party applications access to their resources without sharing their credentials, enhancing security by avoiding direct exposure of sensitive information. Since its inception in 2007, OAuth has evolved from version 1.0 to the widely used OAuth 2.0, with OAuth 2.1 in development, which introduces security improvements such as mandatory PKCE and the removal of insecure grant types. The framework defines four primary roles: resource owner, client, resource server, and authorization server, facilitating a secure flow of authorization through tokens and scopes. OAuth is often compared to SAML, with OAuth focusing on authorization and using lightweight JSON Web Tokens (JWTs), while SAML is more enterprise-focused, handling both authentication and authorization through XML. OpenID Connect (OIDC) builds on OAuth for authentication, allowing disparate systems to share user authentication states seamlessly. Despite its advantages, OAuth implementation can be complex and prone to misconfigurations, which can be mitigated by tools like Descope that offer secure, no-code solutions for integrating OAuth into applications.