All about CAPTCHA

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/.

Most of the business websites wish to provide a feature on their site for visitors to drive response while avoiding spam. Posting an email on your website is a sure shot invitation for spammers. There are assortments of tricks and methods to "conceal" your email address so that spammers find it difficult to track.

The best method for doing this is to embed Java script in the web page to capture the email address when the page is displayed to the visitor. A more sophisticated method is to use CAPTCHA along with the website forms. It's a common sight on big websites which require you to sign up.

When you register with these sites you are 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. This is how this form distinguishes between a human and a machine because only a human can make out these indistinct characters. Therefore it is construed as automatically authenticated and submitted by a human visitor rather than some computer generated program.

CAPTCHA helps to avert bots from misusing Internet services. Bots are programs that model as humans on the Internet. They 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 and accumulate personal information and post links to promotional sites. They create worms, break password systems, assault confidentiality, and deplete resources. You can avoid all this with CAPTCHA Plugin. You can customize your CAPTCHA with preferred colors and fonts. You can also from a whole range 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].

Inserting CAPTCHA code in your web pages provides a dependable method to authenticate that the registration is being tendered by a human being and not by some computer generated process. The use of CAPTCHA is therefore becoming increasingly popular.

About the Author:

Oleg is an expert on CAPTCHA design and development. Click to find out more about his new CAPTCHA Plugin technology.