Perhaps I should first start out with a few little tips of terminology that I use.

Public Class SlideBox
    Public BoxHeight, BoxWidth, BoxLength As Integer
    'Set these when you want
    Private mbox As Integer
    Private IsClosed As Boolean
    'These are private and used for returning data here
    Public Sub CloseBox()
        IsClosed = True
        'Closes the box :}
    End Sub
    Public Property BoxNumber() As Integer
        Get
            Return mbox
        End Get
        Set(ByVal Value As Integer)
            mbox = Value
        End Set
    End Property
    'BoxNumber is set just like a regular property.
    Public ReadOnly Property BoxVolume() As Integer
        Get
            Return BoxHeight * BoxWidth * BoxLength
        End Get
        'ReadOnly has no Set statement.
    End Property
    Public Function BoxDensity(ByVal Mass As Integer) As Single
        Dim Vol As Single = Convert.ToSingle(BoxHeight * BoxWidth * BoxLength)
        Return Convert.ToSingle(Mass) / Vol
        'Must convert both items to Single.
    End Function
End Class

This class will give the following members if you use this instance from another class:
BoxHeight, BoxWidth, BoxLength, CloseBox, BoxNumber, BoxVolume, BoxDensity
Of these 7 members, BoxDensity and CloseBox are methods, denoted by the little diamond.
Of course, you will also see a GetType method within MVS 20##, which you'll get in any class. They facilitate the conversions to and from object.
The other 5 are properties, and here's a little schematic of the class:

The gold properties there are the two private properties, mbox and IsClosed.

Shared Members

Now, suppose that I add two methods to the class like this:

    Public Shared Function Density(ByVal Mass As Integer, ByVal Volume As Integer) As Single
        'D = M / V
        Return Convert.ToSingle(Mass) / Convert.ToSingle(Volume)
    End Function
    Public Shared Function Volume(ByVal Mass As Integer, ByVal Density As Single) As Integer
        'Switch D with V: V = M / D
        Return Convert.ToSingle(Mass) / Density
    End Function

The Shared Function is accessible outside of the Class.  For example:

Public Class Ugh
    Private X As Single
    Public Sub New()
        X = SlideBox.Density(500, 200)
        'X now contains 2.5.
    End Sub
End Class

Overloaded Methods

An overloaded method is one that lets you have multiple distinct parameter sets.  Suppose that I wanted to calculate a potential energy for my box.  U = mgh.  I can easily make a function to do this:

    Public Const Gravity As Single = 9.81
    Public Function PotentialEnergy(ByVal Mass As Integer, ByVal BoxAltitude As Single) As Single
        'If you must know, I used Singles because g = 9.81 m/(s^2).
        Return Convert.ToSingle(Mass) * BoxAltitude * Gravity
    End Function

Now, suppose I want to calculate the potential energy with respect to a certain height... if the box is sitting on a hill that is 10 high, but I want to find the energy the box will have if it went to 7 m...

    Public Overloads Function PotentialEnergy(ByVal Mass As Integer, ByVal BoxAltitude As Single) As Single
        'If you must know, I used Singles because g = 9.81 m/(s^2).
        Return Convert.ToSingle(Mass) * BoxAltitude * Gravity
    End Function
    Public Overloads Function PotentialEnergy(ByVal Mass As Integer, ByVal BoxAltitude As Single, ByVal ReferPoint As Single) As Single
        Return Convert.ToSingle(Mass) * Gravity * (BoxAltitude - ReferPoint))
    End Function

And I can call it like this:

Public Class Ugh
    Private X As Single
    Public Sub New()
        Dim SB As SlideBox = New SlideBox
        X = SB.PotentialEnergy(50, 14.2)
        'X contains 6965.1
        X = SB.PotentialEnergy(50, 14.2, 9.2)
        'X contains 2452.5
    End Sub
End Class