> pls help me what is the difference between MDI and SDI pls give me
> answer about this
Doesn't google work today?
MDI = "Multiple Document Interface"
SDI = "Single Document Interface"
MDI is when your application consist of an MDI parent-form
that contains all the other window/forms that the app consists of.
SDI is stand-alone, ordinary windows/forms that exists independently
of each other.
VB6 can be both... Select "Tools --> Options", and click on the
"Advanced" tab... See the difference for yourself.