The Security Assertion Markup Language (SAML) is an open standard that allows security credentials to be shared by multiple computers across a network. It describes a framework that allows one computer to perform some security functions on behalf of one or more other computers:
Authentication: Determining that the users are who they claim to be
Authorization: Determining if users have the right to access certain systems or content
Strictly speaking, SAML refers to the XML variant language used to encode all this information, but the term can also cover various protocol messages and profiles that make up part of the standard.