Procedure is a sub-routine which contains set of statements. Usually Procedures are written when multiple calls are required to same set of statements which increases re-usuability and modularity.

Procedures are of two types.

1. Functions

Functions return a value when they are called.

[accessModifiers] Function functionName [(parameterList)] As returnType
   'code
End Function

Example

Public Module Program
	Public Sub Main(args() As string)
	    Dim x As Integer = 10
      Dim y As Integer = 20
      
      Dim res As Integer
      
      res = sum(x,y)
      Console.WriteLine("Sum : {0}", res)
      Console.ReadLine()
  End Sub
	
	Function Sum(ByVal a As Integer, ByVal b As Integer) As Integer
      
      Dim result As Integer
      
      result = a + b
      Sum = result
   End Function
   
End Module

Check Result here

2. Sub-Procedures

Sub-procedures are similar to functions but they don't return any value.

Sub ProcedureName (parameterList)
'Code
End Sub

Example

Public Module Program
	Public Sub Main(args() As string)

      greetings("Foo")

  End Sub
	
	Sub greetings(ByVal name As String)
      
     Console.WriteLine("Hello {0}", name)
     
   End Sub
   
End Module

Check Result here