All about CAPTCHA

Posted by Fizaazida | Saturday, August 02, 2008 | 0 comments »

By: Oleg

CAPTCHA is the acronym of ‘Completely Automated Public Turing test to tell Computers and Humans Apart.’ It is a kind of test based on challenge responses. From the response it gets it can make out whether the user is human or not. In an ordinary kind of CAPTCHA the user has to key in the letters of a fuzzy image to see them emerge on the screen. Often, the user has to supplement masked series of letters or digits to do that. Only then they will emerge on the screen.

CAPTCHA can not only create these tests automatically but also store them. The basic principle is that they admit all humans and discard almost all machines since humans can usually read tarnished images, but OCR machines cannot.For more details please visit http://www.protectwebform.com/.

Spammers are a nuisance for both the business websites as well as the visitors. While the business websites wish to provide a feature on their site for visitors to drive response and try to ensure protection from spam. But, if you post an email on your website, you are sure to invite spammers. In order to avoid this, websites use an assortment of tricks and methods to conceal your email address to make it difficult for spammers to track.

One way to do it is by embedding Java script in the web page to capture the email address when the page is displayed to the visitor. An enhanced alternative is to use CAPTCHA along with the website forms. You must have seen this feature in use on big websites which require you to sign up.

The person registering with these sites is required to identify and enter some indistinct characters shown on the screen for confirmation before submitting the form. The logic here is that computer generated programs will not be able to identify these unclear characters and alphabets. The form is therefore construed as automatically authenticated and submitted by a human visitor rather than some computer generated program.

A CAPTCHA is intended to avert bots – programs that model as humans on the Internet – from misusing Internet services. Bots are created not to rule but to sell, sign up for numerous free email accounts every moment, sending millions of Spam messages from them. They penetrate chat rooms, accumulate personal information and posts links to promotional sites. They create worms, break password systems, assault confidentiality, and deplete resources. With CAPTCHA Plugin, you can customize your CAPTCHA with preferred colors and fonts. You can also decide among loads of image types. [See http://www.protectwebform.com/plugin_wordpress].

It was ProtectWebForm that invented a technique of improving the CAPTCHA to make work easier. It called "Smart CAPTCHA". Since it is very difficult for most spam robots to carry out scripts, using an easy script which fill up the CAPTCHA fields and conceal the image and the field from human eyes was planned. The "Smart CAPTCHA” is a case of safety through shadows. They defend your site because authors do not come across the exact kind of JavaScript in question. Developers recommend joining the CAPTCHA with JavaScript support. [See http://www.protectwebform.com/smartcaptcha].

Once you have inserted the CAPTCHA code in your web pages you can be sure that the registration is being tendered by a human being and not by some computer generated process. No wonder, the use of CAPTCHA is becoming increasingly popular.

Keyword Articles: http://www.keywordarticles.org

Oleg is an expert on CAPTCHA design and development. Click to learn more about his ingenious new Smart CAPTCHA technology.

0 comments