sessionID difference

SessionID always change, on page reload / postback, next page in .NET 2.0 even for same user.

However, if someone actives the session, then the SessionID will keep same the that one.

for example: Button1 was clicked.

    protected void Button1_Click(object sender, EventArgs e)
    {
        StudentInfo _objStudentInfo = new StudentInfo(Int32.Parse("67"), "lk");
        Session["objStudentInfo"] = _objStudentInfo;
    }

sessionID will maintain!