captcha code is simply a verification code that is used as security reason that the user that uses the site is real a human..
Captcha code is a security question which is ask by a site to check the visitor is bot or a human, to check the visitor is human and the site is not using by a software.
Captcha code is for security purpose. It helps to know that user which is filling the form is a human... It inserts in a website to protect it from the spam mails
it is when you have to enter the weird text or numbers that you see in a image. This could be to post a comment or send a contact email to someone. If you have wordpress then there are plugins to allow you to use these feature to avoid spam and bots
It's just the letters of distorted images that helps to differentiate the human started queries and automated software queries.. This helps in preventing the email-spams...
Captcha code can be an image, question, some puzzle or can be anything which can be identified by a human. It is integrated in a website to identify whether the user is a bot or human. Bots are not capable of answering captcha queries.