We mainly use Azure Active Directory for authentication, identity management, and single sign-on. A user can use a local Active Directory password to sign into other platforms, like Zendesk or Zoom. These on-premise users are synced to Azure Active Directory. We have some other users who only use cloud, so they don't have instances on-premise, i.e., they are pure cloud. Both of these types of users can authenticate their credentials with other applications and single sign-on.
We use Microsoft solutions, such as Microsoft Endpoint Manager for mobile device management (MDM), Microsoft Defender, and Advanced Threat Protection (ATP). For our customers and clients, we do something similar. We also send logs from Microsoft 365 to different SIEMs.
We sync users from on-premise using AD Connect sync. We sync them to Azure Active Directory, where we have some instances.