Boolean

The boolean data type can contain either the value True or False.
This data type uses 2 bytes.
The keywords True and False are built-in constants.
The default value is False (or zero).
Any value that is not equal to zero is equivalent to True.
True = -1
False = 0
A boolean variable is often used to check the condition in an If-Then-Else statement.

Dim bMyValue As Boolean   'defaults to False  
bMyValue = True 

If (bMyValue = True) Then 
   Call Msgbox("true") 
Else 
   Call MsgBox("false") 
End If 

Call MsgBox(VBA.CInt(True)) 
Call MsgBox(VBA.CInt(False)) 

Conversion Function

The CBOOL function returns an expression converted to an boolean data type.