Native captcha for your form in Magento 1.7

Magento 1.7 came with a lot of changes and new features – one substantial module that was added by default is captcha. So, we would like to shed the light on this amazing feature. You know how many robots/spam bots browse the internet searching unprotected forms. Argh.. Therefore, if you have opened form for unregistered users you need to protect it with captcha to avoid spam attacks :)