Azure AD B2C stands for Azure Active Directory Business-to-Consumer. This component is responsible for handling user account sign-up, sign-in, profile edit and password reset functionalities outside the applications developed to meet any specific functionality. AAD B2C has its own login portal management which can be customized to a certain extent to change the look and feel as required by customers.
Azure AD B2C is a directory service that leverages identity stores outside of your company. It is an authentication service for publicly facing applications. In addition to provide authentication service for local email accounts, it also integrates with other third-party identity providers such as Google+, Facebook, Amazon, or LinkedIn to provide a one-stop shop for authentication. It acts as an alternative to the burden of having to manage authentication and account details yourself.
Figure 1: Basic Solution Architecture
It serves as a direct replacement for managing your own authentication and account database. It also replaces using SDKs to manage authentication using Facebook, Google, or some other identity provider. All of this is to make it easier for the consumer to sign in and use your application.
Some of the major advantages of using Azure AD B2C are:
Azure AD B2C default login screens look like:
Figure 2: Sign in Page
Figure 3: Sign Up Page
Figure 4: Verification Page
Figure 5: Password Reset Page
The basic steps to setup Azure AD B2C are:
For a full guide,the Microsoft documentation is the best place to start.