Internal implementation of stil iterators

I am very confused as to what an iterator implementation looks like ?
Does the class have a pointer ?
When we say that the iterators are tied in with the containers, does it mean that every container has a private member which of type iterator ?

I am trying to practice how all the stl containers and algorithms are implemented internally

Please pardon the subject it should be stl instead of stil.. I dont know how to go back and edit the header..

Have you checked the source code? Its all templated and in header files supplied with your compiler.