php upload and download

                                        INDEX.PHP <?php session_start (); ? > <! DOCTYPE   html > < html   lang = " en " > < head >     < meta   charset = " UTF-8 " >     < title >login system</ title >     < link   rel = " stylesheet "   href = " css/style.css " > </ head > < body >     < nav >         < a   href = " #home " >< img   src = " image/logo.jpg "   id = " logo " ></ a >         < ul >             < li >< a   href = " #home " >Home</ a ></ li >             < li >< a   href = " #about " >About</ a ></ li >             < li >< a   href = " #contact " >Contact</ a ></ li >         </ ul >         < div   class = " login " >             < form   action = " includes/login.inc.php "   met