SAML (Security Assertion Markup Language) is a format used in online security. SAML creates a standard way to prove identity and pass it along to other applications. It's made of assertions about a user or requesting party. Applications use these assertions to determine if a user is eligible to access resources on a server. Thus, SAML helps ensure only who is allowed to access information can access it. SAML is XML-based and used by Identity Providers in conjunction with service providers. SAML is an open format standardized by OASIS and adopted by many top-tier cloud technology companies.