This guide will explain what CAPTCHA is and what it is used for.
What is CAPTCHA?
A CAPTCHA is a test to determine whether the user is a computer or a human. The most common type of CAPTCHA is an image of obscured letters or numbers displayed in a box. A user must type the sequence correctly before accessing the website or submitting data. As automated bots are not able to read these images, they are prevented from misusing the website’s resources.
The following image is an example of a common type of CAPTCHA:
CAPTCHA example
You should consider adding CAPTCHA protection to your website if it has any of the following:
● Surveys or polls.
● Pages that accept file uploads or downloads by users.
● Any other pages that accept user-submitted data.
● Forms that process user-submitted data, including e-mail forms, comment forms, and registration forms.
CAPTCHA IMPLEMENTATIONS
reCAPTCHA from Google is one of the most popular among numerous methods for implementing CAPTCHA for PHP. For general information about reCAPTCHA, please visit http://www.google.com/recaptcha. For specific information about implementing reCAPTCHA with PHP, please visit https://developers.google.com/recaptcha/intro