On some sites there is an image that is dynamically generated at page load,
which simply has a few random characters like "a5J7" printed on it (which
change with each page refresh), and the user must enter in those characters
they see in a textbox as if it was a password. This allows the website to
confirm that the visitor is a human, and not just an automated script.
Does anyone know how (if?) this can be done with PHP? my Googling wasnt very
fruitful :(