Azure Information Protection (AIP) provides the encryption service, Azure Rights Management, that's used by Microsoft Purview Information Protection and the following capabilities:
The Microsoft Information Protection SDK extends sensitivity labels to third-party apps and services. Developers can use the SDK to build built-in support for applying labels and protection to files.
For example, you might use the MIP SDK for:
A line-of-business application that applies sensitivity labels to files on export.
A CAD/CAM design application that provides support for built-in labeling.
A cloud access security broker or data loss prevention solution that reasons over data encrypted with Azure Information Protection.