How to define department roles hierarchy in SharePoint 2010 and get user's Manager information in c#?

Question

Having the SharePoint site where need to configure the access to the lists and libraries according the roles and permissions. How to define following hierarchy in SharePoint 2010 site. What groups I need to define ?

HR Department :
User1 -HR Manager
User2 -HR Assistant Manager
User3 -HR Team Lead
User4 -HR
User5 -HR
User6 -HR
User7 -HR 

Edited: Need to scenario like when logged in user sending mail to any other user then should get his manager information too, to keep him CC.

Answer 1

<script type="text/javascript" src="../../JSLibrary/jquery-1.3.2.min.js"></script>

<script type="text/javascript" src="../../JSLibrary/jquery.SPServices-0.4.8.min.js"></script>

<script type="text/javascript">

    $(document).ready(function () {

        var managerName;

        var userName = $().SPServices.SPGetCurrentUser();

        $().SPServices({

            operation: "GetUserProfileByName",

            async: false,

            AccountName: userName,

            completefunc: function (xData, Status) {

                managerName = $(xData.responseXML).text();

                var managerLength = managerName.length;

                var indexofManager = managerName.indexOf("Manager");

                managerName = managerName.substring(indexofManager + 13, managerLength);

                var indexOffalse = managerName.indexOf("false");

                managerName = managerName.substring(0, indexOffalse);

            }

        });

        var peoplepicker = $("tr:contains('Reporting Manager'):last").find("div[title='People Picker']");

        peoplepicker.html(managerName);

    });

Above code will help you to get manager.You can set it to any of the control & get it from there in Client side code. I had set it to SharePoint People Picket for an example here.

It is surely working in SharePoint Foundation 2010.