1. Choose the "Developer" tab and open the VBA editor. If you don't locate the "Developer" tab, follow this guide. The following window will then open.
   
2. To write our first macro, choose "Instert" -> "Module".
   
   
3. First, we will make a Sub procedure that we may later add to our button. All Sub procedures have to begin with Sub and end with End Sub. A Sub can not return a value, and may be compared with a program in other programming languages, where as a function is an alternative. We then call the MsgBox function to create a new window displaying our message.
   
   
   

4. Lets now return to our Excel sheet to add the button. The insert button feature is shown in the image below.

   Tips: To align the size of the button with existing cells, hold down ALT while resizing. This applies to all sizings!

   
   

5. A new window will open. Choose the "Hello World" macro we just created and click "OK".
   
   
   
6. We may then rename our button by right-clicking on it and choosing "Edit text".
   
   
   
   
7. Finally, we can test our macro by clicking on the button. A window displaying the message "Hello World!" should then open.
   If it does, congratulations! You have just made your first macro using VBA.
   
   

Hello World video tutorial (no audio)

1. Make a simple sheet to duplicate.
   
2. Locate the Developer tab, and click on Record Macro.
   
3. A new window should then open. You always want to name your macros something meaningful, making it easy to understand what macro does by just the name. This applies especially when the number of macros increase. Click then OK.
   
4. VBA is now recording our actions.
   
5. To duplicate a sheet in Excel, right-click on the sheet name, and click on Move or Copy...
   
6. In the window appearing, mark off for (move to end) on the location, and tick off for Create a copy. Click then OK.
   
7. A duplicate has now been made.
   
8. Time to stop the recording. This is done by clicking on Stop Recording, located the same place as the Record Macro was.
   
9. To look at the code created by VBA, open the Visual Basic Editor.
   
10. Open Module1, and the code is displayed.
    
11. If we want to run the code again, we can click somewhere inside the subroutine DuplicateSheet() and then click on the play icon.
    
12. Our Sheet1 is then duplicated again.
    
13. If we wanted, we could also have made e.i. a button and attached our macro to it, just as in the Hello World tutorial.

Before we look at the different variable declarations, we need to establish the difference between the words explicit and implicit.

• explicit is defined as: "stated clearly and in detail, leaving no room for confusion or doubt."
• implicit is defined as: "implied, rather than expressly stated"
  

When coding in Visual Basic, you are by default not obligated to declare your variables before using them. This an example of an implicit variable declaration.

MyVariable = 10

When doing so, VBA will automatically declare it as a variant type, provided that the variable has not been declared before. This is a nice feature, but may cause trouble when writing larger scripts. Let's look at an example:

We have already written a lot of code using the variable "MyVariable". If we were to misspell "MyVariable" with "MyVaiable" once, VBA will think of it as a new variable declared implicitly, and declare it automatically, thus not informing us of our misspell.

MyVariable = 4
'We want to multiply MyVariable with 10
MyVaiable = MyVariable * 10

'... lots of code

'When we finally display MyVariable, thinking it equals 40
MsgBox MyVariable
'4 is displayed

To avoid this problem, we can use the Option Explicit Statement. It ensures that all variables must be explicitly declared by using the Dim, Private, Public, ReDim or Static statements. Otherwise, it will display an error at compile time.

If used, the "Option Explicit" statement must appear in a module before any procedures.

Option Explicit

Sub Example()

'Explicitly declaring MyVariable as an integer
Dim MyVariable As Integer

MyVariable = 4
'We want to multiply MyVariable with 10
MyVaiable = MyVariable * 10		' We will encounter an error at this line.

'... lots of code

'When we finally display MyVariable, thinking it equals 40
MsgBox MyVariable
'4 is displayed

End Sub

Compiling the code above will result in the following error message.

If you want to make all your modules have the "Option Explicit" statement without having to remember to write it yourself, follow these instructions:

1. In your VBA editor, go to "Tools" → "Options".
   
   
   
2. Tick the "Require Variable Declaration" box. Click "OK".
   

Sub Example1()

MsgBox "Displaying a message!"	' When we only want to display a message, we don't need several parameters.

End Sub

Example 1 displayes the following dialog box:

Sub Example2()

Dim Msg, Style, Title, Response, MyString

Msg = "Do you want to continue ?"                   ' Define message.
Style = vbYesNo + vbCritical + vbDefaultButton2     ' Define buttons.
Title = "MsgBox Demonstration"                      ' Define title.
Response = MsgBox(Msg, Style, Title)                ' When we have several parameters, 
													' we have to call MsgBox as: MsgBox([parameters]).
If Response = vbYes Then    ' User chose Yes.
    MyString = "Yes"        ' Perform some action.
Else                        ' User chose No.
    MyString = "No"         ' Perform some action.
End If

End Sub

Example 2 displayes the following dialog box: