Scope of Variable

'Procedure Scope
Sub TestSub()
        Dim X As Long
        Dim Y As Long
       
        X = 1234
        Y = 4321
        MsgBox "X: " & X & "Y: " & Y
End Sub
'Module Scope
'Module scope means that a variable can be declared before and outside of any procedure
'in a regular code module. If you use Private or Dim to declare the variable, only procedures
'that are in the same module can access that variable. Since a module level variable is not
'part of any procedure, it will retain its value even after the procedure that changes its
'value has terminated. For example,
'Dim ModVar As Long
'Private ModVar As Long

'Project scope
'Project scope variables are those declared using the Public keyword.
'These variables are accessible from any procedure in any module in the project.
'In Excel, a Project is all of the code modules, userforms, class modules, and object
'modules (e.g,. ThisWorkbook and Sheet1) that are contained within a workbook.
'If you want a variable to be accessible from anywhere within the project, but not accessible
'from another project, you need to use Option Private Module as the first line in the module
'Global Scope
'Global scope variables are those that are accessible from anywhere in the project that
'declares them as well as any other project that references the first project. To declare
'a variable with global scope, you need to declare it using the Public keyword in a module
'that does not use the Option Private Module directive.