Difference between MDM and MAM
Microsoft 365 Business Premium offers a number of ways for you to protect your business data. See Overview of Microsoft 365 Business Premium for more about the various protections that are automatically set up, and what you can set up yourself to further protect your business. You can also onboard devices to Microsoft Defender for Business to protect your Windows devices and the data in your mobile devices. For more information, see Onboard enrolled devices to Microsoft Defender for Business.
Mobile device management or MDM
Microsoft 365 Business Premium lets you set up policies that protect data on your Windows 10 and 11 devices. When a device is under mobile device management, you control the entire device, and can wipe data from it, and also reset it to factory settings. For more information, see Choose the device management solution that's right for you and Set up and secure managed devices.
Mobile application management or MAM
Mobile application management lets you control your business data in your users' personal devices, such as iPhones and Androids, and their personal Windows computers. You can use application management policies to prevent your users from copying business data from Microsoft 365 apps to their personal apps. You can also remove all data from the Microsoft 365 apps on their personal devices. For more information, see Choose the device management solution that's right for you and Set up and secure managed devices.