Sgn

The Sgn function takes any number as its argument, and returns an integer. It is used to determine the sign of a number. If you send the function a negative number, it returns a -1, if you send the function a positive number, it returns a 1, and if you send the function , it returns 0. An example of the function:
Private Sub cmdReturnSign_Click()
     Dim x As Double

     x = 2465
     lblSign.Caption = Sgn(x)     'This causes the caption to display 1

     x = -3.141592653589793238462643383279
     lblSign.Caption = Sgn(x)     'This causes the caption to display -1     

     x = 0
     lblSign.Caption = Sgn(x)     'This causes the caption to display 0
End Sub
This concept is useful outside of Visual Basic and Computer Science, and is also used by mathematicians. "Signum" can be used to make long, complicated equations less so.