$_REQUEST (or) $_GET functions in php
i am install xampp recently 
 
i will write a function in  php

    $value=$_GET['value'];

but it shows an error "Undefined index" 

i will also try $_REQUEST function

plse help me
$_REQUEST (or) $_GET functions in php
===

i am install xampp recently 
 
i will write a function in  php

    $value=$_GET['value'];

but it shows an error "Undefined index" 

i will also try $_REQUEST function

plse help me