Security assertion markup language (SAML) is an open standard for exchanging authentication and authorization data between parties, specifically between an identity provider and a service provider. SAML enables single sign-on (SSO), allowing users to authenticate once and gain access to multiple applications or services. It uses XML-based assertions to pass information about user authentication, entitlements, and attributes, facilitating secure and seamless access across different domains. By standardizing the communication of security credentials, SAML enhances interoperability, simplifies user access management, and improves the security of federated identity systems.