Dim Foo As Range

With Foo
'All below relates to Foo: Because "With."
   .Value = Bar   'Value is a Property of a Range
End With   '(Not using Foo now)
The leading Dot ( .) inside the With... End With relates Properties and Methods to the Object (Foo,) that the With is concerned about.

For example: 
Dim Foo As Collection

With Foo
   .Add Bar   'Add is a Method of Collections
End With