Thanks for reaching out to the community forum.
To answer your question, Azure AD B2C is a standalone service, and it is indeed included as part of the Azure Active Directory External Identities service, which is a component of Microsoft Entra. Azure AD B2C and Microsoft Entra IDs are separate entities and serve different purposes within the Azure service, they are both part of the broader Azure Active Directory ecosystem.
With Azure AD B2C, businesses can allow customers to sign up and sign into their applications using different ways to sign up and log in to their applications. For example, customers can use their Facebook or Google accounts to log in, or they can use their work or school account if their organization uses Azure AD or Active Directory.
Users registered with Azure AD B2C are treated as Azure AD B2C users and not as Microsoft Entra’s Entra IDs.
I hope this answer helps! If you have any further questions, please feel free to ask.
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