Microsoft Azure Active Directory (Azure AD) is a cloud-based identity and access management service provided by Microsoft. It helps organizations manage user identities and control access to resources, applications, and services. Azure AD enables single sign-on (SSO), allowing users to log in once and access multiple applications without needing to enter their credentials repeatedly. Azure AD supports various authentication methods, including multi-factor authentication (MFA) for enhanced security. It integrates with numerous applications, both in the cloud and on-premises, making it easier for businesses to manage user access and ensure that only authorized individuals can access sensitive information and resources.