Tag for miscelaneous use.

A Variant value.  

object.Tag [= value]

The Tag Property syntax has these parts:

Tag property can store arbitary data and hold it for your during message lifetime. If you need to hold additional information about message, you should create Class (in VB) with members of your choice, create instance of that class and just pass it's reference to this property. That way as long as message exists you will be able to access your data.