All about CAPTCHA

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 create and score tests automatically. They admit all humans and discard almost all machines. Humans can usually read tarnished images, but OCR machines cannot. [You can find out more details in 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.

The greatest advantage of CAPTCHA is that it averts 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 get into chat rooms; they accumulate personal information; and they post links to promotional sites. They create worms, break password systems, assault confidentiality, and deplete resources. If you want to avoid all these dangers you can customize your CAPTCHA with colors and fonts of your choice. You can also choose the image you like, with CAPTCHA Plugin. For furher details visit http://www.protectwebform.com/plugin_wordpress.

Smart CAPTCHA is a technique of improving the CAPTCHA to make work easier. It was proposed by ProtectWebForm. They recommend that you join the CAPTCHA with JavaScript support. They planned to use an easy script, which fills up the CAPTCHA fields and conceals the image and the field from human eyes because most spam robots find it difficult to carry out scripts. They have used the method of safety through shadows. They defend your site because authors do not come across the exact kind of JavaScript in question. For furher details visit 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.

Article Source: http://www.rightarticle.com

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