SAML is a quite general framework to convey security information between online actors. While it is being used for web services and other standards, its key application area is the web-based single-sign-on (WebSSO) use case. Over the time it evolved into a rich ecosystem that comprises a set of specifications and profiles, products, tools, libraries and services. An overview of these can be found here:

SAML Interoperability and Deployment Profiles (includes an overview of SMAL standards)
SAML-based products and services (Overview of products, tools and services on Wikipedia)

Browser not supported