Renaming PHP Uploads

//This line assigns a random number to a variable. You could also use a timestamp here if you prefer.
$ran = rand () ;

//This takes the random number (or timestamp) you generated and adds a . on the end, so it is ready of the file extension to be appended.
$ran2 = $ran.".";

//This assigns the subdirectory you want to save into... make sure it exists!
$target = "images/";

//This combines the directory, the random file name, and the extension
$target = $target . $ran2.$ext;

Index: Renaming PHP Uploads

1. Uploading the file
2. Finding the Extention
3. A Random File Name
4. Saving the file with the new name