I'm making something that retrieves the URL the user types in, so far it's working. However i noticed there are some characters the browser handles differenty e.g. #,$,%,^,&,*,!,~,@ (ascii chars) etc etc. Is there someway those characters can be used in a URL without causing errors?

Those characters have special meanings in the context of a url. How are you trying to use them?

If you want to fix the problem use:

urlencode and urldecode.

For example:

PHP Code:

<?php
// Preparing a URL.
echo '<a href="http://www.rogem.net/page.php?var='.urlencode("value").'">';

// decoding whats recived.
echo urldecode($_GET['var']);
?>

If your not into people seeing whats being sent, try a Base64 (This is super cool):

PHP Code:

<?php
// Preparing a URL.
echo '<a href="http://www.rogem.net/page.php?var='.base64_encode("value").'">';

// decoding whats recived.
echo base64_decode($_GET['var']);
?>