What is Security Assertion Markup Language (SAML)?

Security Assertion Markup Language (SAML) is an open standard for exchanging authentication and authorization data between security domains, i.e., between an identity provider (IdP) and a service provider (SP). SAML is commonly used to enable single sign-on (SSO) for web-based applications, allowing users to access multiple services with one set of credentials. It uses XML-based assertions to pass user identity and attribute information from the IdP to the SP, allowing the SP to make authorization decisions without requiring the user to directly authenticate with it.