A short review of 5 free captcha generators that can help you to protect your site from automated spam posts, registrations and so on.

This captcha download guide include the most recommended (free and non-free) captcha scripts and codes you can download and implement in your website or blog to prevent submission forms abuse.

Recaptcha (or reCAPTCHA) is the system that uses the millions of Captcha texts already deciphered by human internet users for the noble cause of digitizing books, newspaper archives and radio shows. ReCptcha is the little comfort we are given for all those challenging captcha texts; thanks to the time and efforts spent by millions everyday [...]

Capthas are not very visually challenged friendly. When the average sighted internet user who is asked to type a couple of distorted half-erased words often cannot tell between l and I, an o and a 0, just imagine what the bespectacled person has to go through when he is about to send a comment or [...]

A new image based captcha plugin for Wordpress by Confident Technologies…

Captcha script is a service that can help you to write your own captcha for your site or any other online platform you own, without having to be an expert or learn a special programming language for that purpose.

Open Source Captcha allows web sites owners to use free programs to create Captcha for security reasons. This is just a short list of captcha open source resources…

Recaptcha is a system which uses Captchas to digitalize books text and pages in order to ensure the user is not a computer or robot but a human being.

Audio Captchas are an alternative for people who suffer from sight impairment and thus are unable to solve regular textual or image Captchas

Captcha is known for its efficiency in ensuring proper use of websites and online application by validating that the user is human and not a bot or some other automatic machine.
This article lists some of the security applications / uses of CAPTCHA:
Comments spam prevention
Comments spam is used in blogs and forums mostly for raising search [...]