Security Assertion Markup Language (SAML, pronounced SAM-el, /ˈsæməl/)[1] is an open standard for exchanging authentication and authorization data between parties, in particular, between an identity provider and a service provider. SAML is an XML-based markup language for security assertions (statements that service providers use to make access-control decisions). SAML is also:
An important use case that SAML addresses is web-browser single sign-on (SSO). Single sign-on is relatively easy to accomplish within a security domain (using cookies, for example) but extending SSO across security domains is more difficult and resulted in the proliferation of non-interoperable proprietary technologies. The SAML Web Browser SSO profile was specified and standardized to promote interoperability.[2] In practice, SAML SSO is most commonly used for authentication into cloud-based business software.[3]
https://en.wikipedia.org/wiki/Security_Assertion_Markup_Language