Vba Excel Message Box

A question about Excel VBA, can anyone explain the mechanics behind

Vba Excel Message Box. All applications are suspended until the user responds to the message box.

A question about Excel VBA, can anyone explain the mechanics behind
A question about Excel VBA, can anyone explain the mechanics behind

All applications are suspended until the user responds to the message box.

All applications are suspended until the user responds to the message box. All applications are suspended until the user responds to the message box.