Early binding - Assigning values to variables during design 
time or exposing object model at design time.

Late Binding - Late binding has the same effect as early 
binding.  The difference is that you bind the object 
library in code at run-time

From a program point of view during early binding the 
function call is resolved at compile time.
In case of late binding the function call is resolved at 
run time with the superclass reference object. It calls the 
function of that subclass whose object is being referred by 
the superclass reference object.

Guys,Can u please Give one example for late binding and
early binding.

BINDING :A process when an object is assigned to an object
variable.
EARLY BINDING:
An object is early bound when it is assigned to a variable
declared to be of that specific object type. Early bound
objects allow the compiler to allocate memory and perform
other optimizations before an application executes. For
example, the following code fragment declares a variable to
be of type FileStream:
'  Create a variable to hold a new object.
Dim FS As System.IO.FileStream
' Assign a new object to the variable.
FS = New System.IO.FileStream("C:\tmp.txt", _
    System.IO.FileMode.Open)
LATE BINDING:
By contrast, an object is late bound when it is assigned to
a variable declared to be of type Object. Objects of this
type can hold references to any object, but lack many of the
advantages of early-bound objects. For example, the
following code fragment declares an object variable to hold
an object returned by the CreateObject function:

' To use this example, you must have Microsoft Excel
installed on your computer.
' Compile with Option Strict Off to allow late binding.
Sub TestLateBinding()
    Dim xlApp As Object
    Dim xlBook As Object
    Dim xlSheet As Object
    xlApp = CreateObject("Excel.Application")
    ' Late bind an instance of an Excel workbook.
    xlBook = xlApp.Workbooks.Add
    ' Late bind an instance of an Excel worksheet.
    xlSheet = xlBook.Worksheets(1)
    xlSheet.Activate()
    ' Show the application.
    xlSheet.Application.Visible = True
    ' Place some text in the second row of the sheet.
    xlSheet.Cells(2, 2) = "This is column B row 2"
End Sub
I took this from this URL:
http://msdn.microsoft.com/en-us/library/0tcf61s1(VS.80).aspx

Early binding - Assigning values to variables during design 
time or exposing object model at design time.

Late Binding - Late binding has the same effect as early 
binding.  The difference is that you bind the object 
library in code at run-time