PAPTCHA stands for Pretty Automated Package to Tell Computers and Humans Apart.
It is under the GPLv2 or later.
The main repo. Development takes place here.
openreCAPTCHA is a sub-project of PAPTCHA, intended to provide a free-software version of reCAPTCHA. It is licensed under the same license that PAPTCHA is under. (GPLv2). This is the repo it will be placed in.