Describe Azure external identities

It is a safe way to include the Identity of other identity providers like Google or Facebook to my Azure Tenant.

Graph from Microsoft: External Identities (opens in a new tab)

• Business-to-business (B2B) collaboration: External user can be invited to access resources. Does not need to be MS IDP.
• B2B direct connect: External user can be invited to access resources. Needs to be MS IDP. They both need to have an Azure Tenant, they will also be able to communicate with each other on MS Teams.
• Microsoft Azure Active Directory business to customer B2C: External user can be invited to access resources. Does not need to be MS IDP. It is used for customer-facing applications.