What is CAPTCHA Code?
It doesn’t matter that you are a programmer, publisher, blogger or just a student. If you are using internet then atleast you should know what’s the meaning of Captcha and why web forms asks to enter it before submission? Read the complete reference of Captcha Code -
The term Captcha stands for ‘Completely Automated Public Turing-test to tell Computers and Humans Apart’. Captcha is the random code generated in the form of an image to protect the web form submission automatically. Captcha gives the protection from unwanted internet bots to accessing websites. Captcha protects the submissions of web forms (like registration form, contact form, business form etc.) through any computer program rather than a human. Captcha ensures that the submission of the web form is done by a human not programmatically or the response from the client side is generated by a human. Almost every secure site like Gmail, Hotmail, Facebook, Twitter etc. places a Captcha Image at the end of the form, the form will not be submitted until you entered the letters, digits or symbols showing on the distorted image.
Captcha is sometimes considered as a Reverse Turing Test, in which it is administrated by a machine (Computer Program) and targeted at a human.
Blogging is an emerging topic and most of the web publishers prefer to do blogging rather than to create a website. The blog commenting is preferred by most of the bloggers to get high PR backlinks and get good enough traffic. Here Spammers takes advantage of Blog commenting and floods spam comments to the blogs. To prevent Blog Comment Spamming (especially for WordPress), Captcha is the secure and easier way although many wordpress plugins (Ex. Akismet) are available to protect from Spammers.
Why we Prefer Captcha rather other security measures? Advantages and Applications of Captcha Code-
1. To Protect Website’s Registration Forms - Many Websites like Hotmail, Gmail, Yahoo, Facebook etc. offers free free registration. It is necessary to protect these website’s registrations so that it ensures the registered user is a human not a program or bot. Captcha Code is used to protect the Registration Form Submission Programmatically.
2. To Prevent Comment Spams in Blogs - Captcha Code is used in the comment form so that only human can comment on a post otherwise spammers can flood hundreds of comments to a single post.
3. To Protect Email Address Scrapping – Spammers crawl the web in the search of Email address posted in the clear text (e.g. firstname.lastname@example.org). You can protect your email address either by using Captcha to hide the email address, one can solve the Captcha before showing the Email address or by using alternative trick to post Email Address in the format of email at website dot com.
4. To Protect from Search Engine Bots - Many Html tags are available to specifying indexing condition to Search engine bots. To prevent a website or specific webpage from search engine crawling, it is desirable to use html meta tag but sometimes it is not completely sure that the webpage is fully protected from search engine crawlers and large companies who needs a high security uses Captcha rather than to use only meta tags to protect their highly public protected and confidential webpages.