Hi, This codes will protect your site from uploading and execute any type of php shell scripts into your upload folder for example , this way will disable any php file in that folder . So , whatever they upload you gonna be in the safe side .the server will deal with php file like txt file !!. This way is very useful in file uploading scripts :

1- make sure that your server is Apache not iis or something else .

2- create file and name it .htaccess  inside upload folder.

3- paste this code in the file

 RemoveHandler .php .php4 .php5 RemoveType .php .php4 .php5 

4- save the file

5- that's it now any php file in that folder is disabled .