The following are C language data types and structures used by Microsoft Exchange. They are provided to help you when writing your code that reads and writes views. Many of the members of these structures are relevant only during run time, but for performance reasons the whole structure is written into the PR_VD_BINARY property. Run-time specific values are reset by Microsoft Exchange when reading views. Although your application can read, manipulate, and write views in whichever way you choose, these structures make development and compatibility easier.