Difference between ByVal And ByRef In UFT

Function test(ByVal var)
    
    info = "test"
    msgbox var
    msgbox info
    
End Function

info = "test1"
Call test(info)  'byval - test1, test  


Function test(ByRef var)
    
    info = "test"
    msgbox var
    msgbox info
    
End Function

info = "test1"
Call test(info)  'byref - test,test

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