Google Recaptcha
What is reCAPTCHA?
reCAPTCHA is a free service from Google that helps protect websites from spam and abuse. A “CAPTCHA” is a test to tell human and bots apart. It is easy for humans to solve, but hard for “bots” and other malicious software to figure out. By adding reCAPTCHA to a site, you can block automated software while helping your welcome users to enter with ease.
