Basic Concepts
Working with Variables
Like all programming languages, VB has variables that store the data used in the programs.  There are many types of variables in VB, such as:

Integer - for whole numbers between -2,100,000 and 2,000,000
Double- for numbers with decimal places ( 3.128325)
String - for text and characters
Boolean - for true and false (binary) data

To use variables, it is also important to understand the concept of scope.  Scope basically is about where the variable belongs.  When you create a variable inside a subroutine (or function) it is considered to have local scope.  This meaning the variable only can be effected by things within that subroutine itself, and not things from the outside, like other subroutines.  You can create more global scope by defining a variable outside of all the subroutines, and within the form itself.  These kinds of variables can be altered by anything within that form, any function or subroutine has access to them.  So how do we define a variable in VB, you do so as the following syntax:

Dim VariableName as VariableType

Examples:
Dim Age as Integer
Dim Alive as Boolean
Dim Pi as Double
Dim PlayerName as String
Dim People (1 to 10) as Integer  (this example shows an array)

Dim Height as Integer, Weight as Integer

How to manipulate Variables

You can do many of things with variables obviously.  If you want to set up a variable with a value from the start all you have to do is something like

Age = 15
CompanyName = "The Crap Factory"

Want to add values together?

Weight = 150
ChineseFood = 20
Weight = Weight + ChineseFood     (Weight now equals 170)

First = "Homer", Last = "Simpson"
Name = First + Last   (Name now equals "HomerSimpson")
Name = First + " " + Last     (Name now equals "Homer Simpson")
Conditional Statements  
= Equal to
<> Not Equal to
> Greater Than
< Less Than
>= Greater or Equal to
<= Lesser or Equal to
If Statements
If Age >= 18 Then
    PersonCanVote = True
Else
    PersonCanVote = False
End If

If Value = 1 Then
    MsgBox "The value is 1"
ElseIf Value = 2 Then
    MsgBox "The value is 2"
Else
    If Value = 10 then
        MsgBox "The Value is 10"
    End If
    MsgBox "The value is something else"
End If

For Loop
For i = 0 to 10
    Value = Value + 1
Next i             

This adds 1 to Value every time until it hits the number 10
Do ... Until Loop
Value = 0
Do
    Value = Value + 1
Loop Until Value > 10 

This adds 1 to Value every time until it hits the number 10
Select Case
Select Case Value
    Case 0:
       Msgbox "Hello"
    Case 1:
    Case 2:
    Case 3:
       MsgBox "I am a Taco"
End Select

This makes a message box appear and say "Hello" if the value of Value is 0, if Value = 1,2 or 3 then it will make a message box that will say "I am a Taco".
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